diff --git a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
index b1a88868b3389..4b647e00032bc 100644
--- a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
@@ -160,6 +160,64 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(ref.current).toBe(span);
   });
 
+  it('can hydrate siblings of a suspended component without errors', async () => {
+    let suspend = false;
+    let resolve;
+    const promise = new Promise(resolvePromise => (resolve = resolvePromise));
+    function Child() {
+      if (suspend) {
+        throw promise;
+      } else {
+        return 'Hello';
+      }
+    }
+
+    function App() {
+      return (
+        <Suspense fallback="Loading...">
+          <Child />
+          <Suspense fallback="Loading...">
+            <div>Hello</div>
+          </Suspense>
+        </Suspense>
+      );
+    }
+
+    // First we render the final HTML. With the streaming renderer
+    // this may have suspense points on the server but here we want
+    // to test the completed HTML. Don't suspend on the server.
+    suspend = false;
+    const finalHTML = ReactDOMServer.renderToString(<App />);
+
+    const container = document.createElement('div');
+    container.innerHTML = finalHTML;
+    expect(container.textContent).toBe('HelloHello');
+
+    // On the client we don't have all data yet but we want to start
+    // hydrating anyway.
+    suspend = true;
+    ReactDOM.hydrateRoot(container, <App />);
+    expect(() => {
+      Scheduler.unstable_flushAll();
+    }).toErrorDev(
+      // TODO: This error should not be logged in this case. It's a false positive.
+      'Did not expect server HTML to contain the text node "Hello" in <div>.',
+    );
+    jest.runAllTimers();
+
+    // Expect the server-generated HTML to stay intact.
+    expect(container.textContent).toBe('HelloHello');
+
+    // Resolving the promise should continue hydration
+    suspend = false;
+    resolve();
+    await promise;
+    Scheduler.unstable_flushAll();
+    jest.runAllTimers();
+    // Hydration should not change anything.
+    expect(container.textContent).toBe('HelloHello');
+  });
+
   it('calls the hydration callbacks after hydration or deletion', async () => {
     let suspend = false;
     let resolve;
diff --git a/packages/react-dom/src/client/ReactDOMHostConfig.js b/packages/react-dom/src/client/ReactDOMHostConfig.js
index 74877c1591e75..79b534d1e1812 100644
--- a/packages/react-dom/src/client/ReactDOMHostConfig.js
+++ b/packages/react-dom/src/client/ReactDOMHostConfig.js
@@ -764,11 +764,23 @@ export function getNextHydratableSibling(
 }
 
 export function getFirstHydratableChild(
-  parentInstance: Container | Instance,
+  parentInstance: Instance,
 ): null | HydratableInstance {
   return getNextHydratable(parentInstance.firstChild);
 }
 
+export function getFirstHydratableChildWithinContainer(
+  parentContainer: Container,
+): null | HydratableInstance {
+  return getNextHydratable(parentContainer.firstChild);
+}
+
+export function getFirstHydratableChildWithinSuspenseInstance(
+  parentInstance: SuspenseInstance,
+): null | HydratableInstance {
+  return getNextHydratable(parentInstance.nextSibling);
+}
+
 export function hydrateInstance(
   instance: Instance,
   type: string,
@@ -917,7 +929,7 @@ export function didNotMatchHydratedTextInstance(
   }
 }
 
-export function didNotHydrateContainerInstance(
+export function didNotHydrateInstanceWithinContainer(
   parentContainer: Container,
   instance: HydratableInstance,
 ) {
@@ -932,6 +944,25 @@ export function didNotHydrateContainerInstance(
   }
 }
 
+export function didNotHydrateInstanceWithinSuspenseInstance(
+  parentInstance: SuspenseInstance,
+  instance: HydratableInstance,
+) {
+  if (__DEV__) {
+    // $FlowFixMe: Only Element or Document can be parent nodes.
+    const parentNode: Element | Document | null = parentInstance.parentNode;
+    if (parentNode !== null) {
+      if (instance.nodeType === ELEMENT_NODE) {
+        warnForDeletedHydratableElement(parentNode, (instance: any));
+      } else if (instance.nodeType === COMMENT_NODE) {
+        // TODO: warnForDeletedHydratableSuspenseBoundary
+      } else {
+        warnForDeletedHydratableText(parentNode, (instance: any));
+      }
+    }
+  }
+}
+
 export function didNotHydrateInstance(
   parentType: string,
   parentProps: Props,
@@ -949,7 +980,7 @@ export function didNotHydrateInstance(
   }
 }
 
-export function didNotFindHydratableContainerInstance(
+export function didNotFindHydratableInstanceWithinContainer(
   parentContainer: Container,
   type: string,
   props: Props,
@@ -959,7 +990,7 @@ export function didNotFindHydratableContainerInstance(
   }
 }
 
-export function didNotFindHydratableContainerTextInstance(
+export function didNotFindHydratableTextInstanceWithinContainer(
   parentContainer: Container,
   text: string,
 ) {
@@ -968,7 +999,7 @@ export function didNotFindHydratableContainerTextInstance(
   }
 }
 
-export function didNotFindHydratableContainerSuspenseInstance(
+export function didNotFindHydratableSuspenseInstanceWithinContainer(
   parentContainer: Container,
 ) {
   if (__DEV__) {
@@ -976,6 +1007,39 @@ export function didNotFindHydratableContainerSuspenseInstance(
   }
 }
 
+export function didNotFindHydratableInstanceWithinSuspenseInstance(
+  parentInstance: SuspenseInstance,
+  type: string,
+  props: Props,
+) {
+  if (__DEV__) {
+    // $FlowFixMe: Only Element or Document can be parent nodes.
+    const parentNode: Element | Document | null = parentInstance.parentNode;
+    if (parentNode !== null)
+      warnForInsertedHydratedElement(parentNode, type, props);
+  }
+}
+
+export function didNotFindHydratableTextInstanceWithinSuspenseInstance(
+  parentInstance: SuspenseInstance,
+  text: string,
+) {
+  if (__DEV__) {
+    // $FlowFixMe: Only Element or Document can be parent nodes.
+    const parentNode: Element | Document | null = parentInstance.parentNode;
+    if (parentNode !== null) warnForInsertedHydratedText(parentNode, text);
+  }
+}
+
+export function didNotFindHydratableSuspenseInstanceWithinSuspenseInstance(
+  parentInstance: SuspenseInstance,
+) {
+  if (__DEV__) {
+    // const parentNode: Element | Document | null = parentInstance.parentNode;
+    // TODO: warnForInsertedHydratedSuspense(parentNode);
+  }
+}
+
 export function didNotFindHydratableInstance(
   parentType: string,
   parentProps: Props,
diff --git a/packages/react-reconciler/src/ReactFiberHostConfigWithNoHydration.js b/packages/react-reconciler/src/ReactFiberHostConfigWithNoHydration.js
index b95fd52d189b5..1392cf8a26083 100644
--- a/packages/react-reconciler/src/ReactFiberHostConfigWithNoHydration.js
+++ b/packages/react-reconciler/src/ReactFiberHostConfigWithNoHydration.js
@@ -29,6 +29,8 @@ export const isSuspenseInstanceFallback = shim;
 export const registerSuspenseInstanceRetry = shim;
 export const getNextHydratableSibling = shim;
 export const getFirstHydratableChild = shim;
+export const getFirstHydratableChildWithinContainer = shim;
+export const getFirstHydratableChildWithinSuspenseInstance = shim;
 export const hydrateInstance = shim;
 export const hydrateTextInstance = shim;
 export const hydrateSuspenseInstance = shim;
@@ -40,11 +42,15 @@ export const clearSuspenseBoundaryFromContainer = shim;
 export const shouldDeleteUnhydratedTailInstances = shim;
 export const didNotMatchHydratedContainerTextInstance = shim;
 export const didNotMatchHydratedTextInstance = shim;
-export const didNotHydrateContainerInstance = shim;
+export const didNotHydrateInstanceWithinContainer = shim;
+export const didNotHydrateInstanceWithinSuspenseInstance = shim;
 export const didNotHydrateInstance = shim;
-export const didNotFindHydratableContainerInstance = shim;
-export const didNotFindHydratableContainerTextInstance = shim;
-export const didNotFindHydratableContainerSuspenseInstance = shim;
+export const didNotFindHydratableInstanceWithinContainer = shim;
+export const didNotFindHydratableTextInstanceWithinContainer = shim;
+export const didNotFindHydratableSuspenseInstanceWithinContainer = shim;
+export const didNotFindHydratableInstanceWithinSuspenseInstance = shim;
+export const didNotFindHydratableTextInstanceWithinSuspenseInstance = shim;
+export const didNotFindHydratableSuspenseInstanceWithinSuspenseInstance = shim;
 export const didNotFindHydratableInstance = shim;
 export const didNotFindHydratableTextInstance = shim;
 export const didNotFindHydratableSuspenseInstance = shim;
diff --git a/packages/react-reconciler/src/ReactFiberHydrationContext.new.js b/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
index f694d8407ecdf..6aad7f03339f5 100644
--- a/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
+++ b/packages/react-reconciler/src/ReactFiberHydrationContext.new.js
@@ -38,6 +38,8 @@ import {
   canHydrateSuspenseInstance,
   getNextHydratableSibling,
   getFirstHydratableChild,
+  getFirstHydratableChildWithinContainer,
+  getFirstHydratableChildWithinSuspenseInstance,
   hydrateInstance,
   hydrateTextInstance,
   hydrateSuspenseInstance,
@@ -45,11 +47,15 @@ import {
   shouldDeleteUnhydratedTailInstances,
   didNotMatchHydratedContainerTextInstance,
   didNotMatchHydratedTextInstance,
-  didNotHydrateContainerInstance,
+  didNotHydrateInstanceWithinContainer,
+  didNotHydrateInstanceWithinSuspenseInstance,
   didNotHydrateInstance,
-  didNotFindHydratableContainerInstance,
-  didNotFindHydratableContainerTextInstance,
-  didNotFindHydratableContainerSuspenseInstance,
+  didNotFindHydratableInstanceWithinContainer,
+  didNotFindHydratableTextInstanceWithinContainer,
+  didNotFindHydratableSuspenseInstanceWithinContainer,
+  didNotFindHydratableInstanceWithinSuspenseInstance,
+  didNotFindHydratableTextInstanceWithinSuspenseInstance,
+  didNotFindHydratableSuspenseInstanceWithinSuspenseInstance,
   didNotFindHydratableInstance,
   didNotFindHydratableTextInstance,
   didNotFindHydratableSuspenseInstance,
@@ -78,8 +84,10 @@ function enterHydrationState(fiber: Fiber): boolean {
     return false;
   }
 
-  const parentInstance = fiber.stateNode.containerInfo;
-  nextHydratableInstance = getFirstHydratableChild(parentInstance);
+  const parentInstance: Container = fiber.stateNode.containerInfo;
+  nextHydratableInstance = getFirstHydratableChildWithinContainer(
+    parentInstance,
+  );
   hydrationParentFiber = fiber;
   isHydrating = true;
   return true;
@@ -92,8 +100,10 @@ function reenterHydrationStateFromDehydratedSuspenseInstance(
   if (!supportsHydration) {
     return false;
   }
-  nextHydratableInstance = getNextHydratableSibling(suspenseInstance);
-  popToNextHostParent(fiber);
+  nextHydratableInstance = getFirstHydratableChildWithinSuspenseInstance(
+    suspenseInstance,
+  );
+  hydrationParentFiber = fiber;
   isHydrating = true;
   return true;
 }
@@ -105,7 +115,7 @@ function deleteHydratableInstance(
   if (__DEV__) {
     switch (returnFiber.tag) {
       case HostRoot:
-        didNotHydrateContainerInstance(
+        didNotHydrateInstanceWithinContainer(
           returnFiber.stateNode.containerInfo,
           instance,
         );
@@ -118,6 +128,14 @@ function deleteHydratableInstance(
           instance,
         );
         break;
+      case SuspenseComponent:
+        const suspenseState: SuspenseState = returnFiber.memoizedState;
+        if (suspenseState.dehydrated !== null)
+          didNotHydrateInstanceWithinSuspenseInstance(
+            suspenseState.dehydrated,
+            instance,
+          );
+        break;
     }
   }
 
@@ -144,14 +162,23 @@ function insertNonHydratedInstance(returnFiber: Fiber, fiber: Fiber) {
           case HostComponent:
             const type = fiber.type;
             const props = fiber.pendingProps;
-            didNotFindHydratableContainerInstance(parentContainer, type, props);
+            didNotFindHydratableInstanceWithinContainer(
+              parentContainer,
+              type,
+              props,
+            );
             break;
           case HostText:
             const text = fiber.pendingProps;
-            didNotFindHydratableContainerTextInstance(parentContainer, text);
+            didNotFindHydratableTextInstanceWithinContainer(
+              parentContainer,
+              text,
+            );
             break;
           case SuspenseComponent:
-            didNotFindHydratableContainerSuspenseInstance(parentContainer);
+            didNotFindHydratableSuspenseInstanceWithinContainer(
+              parentContainer,
+            );
             break;
         }
         break;
@@ -191,6 +218,35 @@ function insertNonHydratedInstance(returnFiber: Fiber, fiber: Fiber) {
         }
         break;
       }
+      case SuspenseComponent: {
+        const suspenseState: SuspenseState = returnFiber.memoizedState;
+        const parentInstance = suspenseState.dehydrated;
+        if (parentInstance !== null)
+          switch (fiber.tag) {
+            case HostComponent:
+              const type = fiber.type;
+              const props = fiber.pendingProps;
+              didNotFindHydratableInstanceWithinSuspenseInstance(
+                parentInstance,
+                type,
+                props,
+              );
+              break;
+            case HostText:
+              const text = fiber.pendingProps;
+              didNotFindHydratableTextInstanceWithinSuspenseInstance(
+                parentInstance,
+                text,
+              );
+              break;
+            case SuspenseComponent:
+              didNotFindHydratableSuspenseInstanceWithinSuspenseInstance(
+                parentInstance,
+              );
+              break;
+          }
+        break;
+      }
       default:
         return;
     }
diff --git a/packages/react-reconciler/src/ReactFiberHydrationContext.old.js b/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
index 3918c014ca146..fd0dd8e99a5b0 100644
--- a/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
+++ b/packages/react-reconciler/src/ReactFiberHydrationContext.old.js
@@ -38,6 +38,8 @@ import {
   canHydrateSuspenseInstance,
   getNextHydratableSibling,
   getFirstHydratableChild,
+  getFirstHydratableChildWithinContainer,
+  getFirstHydratableChildWithinSuspenseInstance,
   hydrateInstance,
   hydrateTextInstance,
   hydrateSuspenseInstance,
@@ -45,11 +47,15 @@ import {
   shouldDeleteUnhydratedTailInstances,
   didNotMatchHydratedContainerTextInstance,
   didNotMatchHydratedTextInstance,
-  didNotHydrateContainerInstance,
+  didNotHydrateInstanceWithinContainer,
+  didNotHydrateInstanceWithinSuspenseInstance,
   didNotHydrateInstance,
-  didNotFindHydratableContainerInstance,
-  didNotFindHydratableContainerTextInstance,
-  didNotFindHydratableContainerSuspenseInstance,
+  didNotFindHydratableInstanceWithinContainer,
+  didNotFindHydratableTextInstanceWithinContainer,
+  didNotFindHydratableSuspenseInstanceWithinContainer,
+  didNotFindHydratableInstanceWithinSuspenseInstance,
+  didNotFindHydratableTextInstanceWithinSuspenseInstance,
+  didNotFindHydratableSuspenseInstanceWithinSuspenseInstance,
   didNotFindHydratableInstance,
   didNotFindHydratableTextInstance,
   didNotFindHydratableSuspenseInstance,
@@ -78,8 +84,10 @@ function enterHydrationState(fiber: Fiber): boolean {
     return false;
   }
 
-  const parentInstance = fiber.stateNode.containerInfo;
-  nextHydratableInstance = getFirstHydratableChild(parentInstance);
+  const parentInstance: Container = fiber.stateNode.containerInfo;
+  nextHydratableInstance = getFirstHydratableChildWithinContainer(
+    parentInstance,
+  );
   hydrationParentFiber = fiber;
   isHydrating = true;
   return true;
@@ -92,8 +100,10 @@ function reenterHydrationStateFromDehydratedSuspenseInstance(
   if (!supportsHydration) {
     return false;
   }
-  nextHydratableInstance = getNextHydratableSibling(suspenseInstance);
-  popToNextHostParent(fiber);
+  nextHydratableInstance = getFirstHydratableChildWithinSuspenseInstance(
+    suspenseInstance,
+  );
+  hydrationParentFiber = fiber;
   isHydrating = true;
   return true;
 }
@@ -105,7 +115,7 @@ function deleteHydratableInstance(
   if (__DEV__) {
     switch (returnFiber.tag) {
       case HostRoot:
-        didNotHydrateContainerInstance(
+        didNotHydrateInstanceWithinContainer(
           returnFiber.stateNode.containerInfo,
           instance,
         );
@@ -118,6 +128,14 @@ function deleteHydratableInstance(
           instance,
         );
         break;
+      case SuspenseComponent:
+        const suspenseState: SuspenseState = returnFiber.memoizedState;
+        if (suspenseState.dehydrated !== null)
+          didNotHydrateInstanceWithinSuspenseInstance(
+            suspenseState.dehydrated,
+            instance,
+          );
+        break;
     }
   }
 
@@ -144,14 +162,23 @@ function insertNonHydratedInstance(returnFiber: Fiber, fiber: Fiber) {
           case HostComponent:
             const type = fiber.type;
             const props = fiber.pendingProps;
-            didNotFindHydratableContainerInstance(parentContainer, type, props);
+            didNotFindHydratableInstanceWithinContainer(
+              parentContainer,
+              type,
+              props,
+            );
             break;
           case HostText:
             const text = fiber.pendingProps;
-            didNotFindHydratableContainerTextInstance(parentContainer, text);
+            didNotFindHydratableTextInstanceWithinContainer(
+              parentContainer,
+              text,
+            );
             break;
           case SuspenseComponent:
-            didNotFindHydratableContainerSuspenseInstance(parentContainer);
+            didNotFindHydratableSuspenseInstanceWithinContainer(
+              parentContainer,
+            );
             break;
         }
         break;
@@ -191,6 +218,35 @@ function insertNonHydratedInstance(returnFiber: Fiber, fiber: Fiber) {
         }
         break;
       }
+      case SuspenseComponent: {
+        const suspenseState: SuspenseState = returnFiber.memoizedState;
+        const parentInstance = suspenseState.dehydrated;
+        if (parentInstance !== null)
+          switch (fiber.tag) {
+            case HostComponent:
+              const type = fiber.type;
+              const props = fiber.pendingProps;
+              didNotFindHydratableInstanceWithinSuspenseInstance(
+                parentInstance,
+                type,
+                props,
+              );
+              break;
+            case HostText:
+              const text = fiber.pendingProps;
+              didNotFindHydratableTextInstanceWithinSuspenseInstance(
+                parentInstance,
+                text,
+              );
+              break;
+            case SuspenseComponent:
+              didNotFindHydratableSuspenseInstanceWithinSuspenseInstance(
+                parentInstance,
+              );
+              break;
+          }
+        break;
+      }
       default:
         return;
     }
diff --git a/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js b/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
index 1cc10a78cb013..29d4fd7e79893 100644
--- a/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
+++ b/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
@@ -150,6 +150,10 @@ export const registerSuspenseInstanceRetry =
   $$$hostConfig.registerSuspenseInstanceRetry;
 export const getNextHydratableSibling = $$$hostConfig.getNextHydratableSibling;
 export const getFirstHydratableChild = $$$hostConfig.getFirstHydratableChild;
+export const getFirstHydratableChildWithinContainer =
+  $$$hostConfig.getFirstHydratableChildWithinContainer;
+export const getFirstHydratableChildWithinSuspenseInstance =
+  $$$hostConfig.getFirstHydratableChildWithinSuspenseInstance;
 export const hydrateInstance = $$$hostConfig.hydrateInstance;
 export const hydrateTextInstance = $$$hostConfig.hydrateTextInstance;
 export const hydrateSuspenseInstance = $$$hostConfig.hydrateSuspenseInstance;
@@ -167,15 +171,23 @@ export const didNotMatchHydratedContainerTextInstance =
   $$$hostConfig.didNotMatchHydratedContainerTextInstance;
 export const didNotMatchHydratedTextInstance =
   $$$hostConfig.didNotMatchHydratedTextInstance;
-export const didNotHydrateContainerInstance =
-  $$$hostConfig.didNotHydrateContainerInstance;
+export const didNotHydrateInstanceWithinContainer =
+  $$$hostConfig.didNotHydrateInstanceWithinContainer;
+export const didNotHydrateInstanceWithinSuspenseInstance =
+  $$$hostConfig.didNotHydrateInstanceWithinSuspenseInstance;
 export const didNotHydrateInstance = $$$hostConfig.didNotHydrateInstance;
-export const didNotFindHydratableContainerInstance =
-  $$$hostConfig.didNotFindHydratableContainerInstance;
-export const didNotFindHydratableContainerTextInstance =
-  $$$hostConfig.didNotFindHydratableContainerTextInstance;
-export const didNotFindHydratableContainerSuspenseInstance =
-  $$$hostConfig.didNotFindHydratableContainerSuspenseInstance;
+export const didNotFindHydratableInstanceWithinContainer =
+  $$$hostConfig.didNotFindHydratableInstanceWithinContainer;
+export const didNotFindHydratableTextInstanceWithinContainer =
+  $$$hostConfig.didNotFindHydratableTextInstanceWithinContainer;
+export const didNotFindHydratableSuspenseInstanceWithinContainer =
+  $$$hostConfig.didNotFindHydratableSuspenseInstanceWithinContainer;
+export const didNotFindHydratableInstanceWithinSuspenseInstance =
+  $$$hostConfig.didNotFindHydratableInstanceWithinSuspenseInstance;
+export const didNotFindHydratableTextInstanceWithinSuspenseInstance =
+  $$$hostConfig.didNotFindHydratableTextInstanceWithinSuspenseInstance;
+export const didNotFindHydratableSuspenseInstanceWithinSuspenseInstance =
+  $$$hostConfig.didNotFindHydratableSuspenseInstanceWithinSuspenseInstance;
 export const didNotFindHydratableInstance =
   $$$hostConfig.didNotFindHydratableInstance;
 export const didNotFindHydratableTextInstance =