diff --git a/packages/outline/src/core/OutlineNode.js b/packages/outline/src/core/OutlineNode.js
index 8ed69b545..3678c4101 100644
--- a/packages/outline/src/core/OutlineNode.js
+++ b/packages/outline/src/core/OutlineNode.js
@@ -447,7 +447,10 @@ export class OutlineNode {
     return parents;
   }
   getPreviousSibling(): OutlineNode | null {
-    const parent = this.getParentOrThrow();
+    const parent = this.getParent();
+    if (parent === null) {
+      return null;
+    }
     const children = parent.__children;
     const index = children.indexOf(this.__key);
     if (index <= 0) {
@@ -456,7 +459,10 @@ export class OutlineNode {
     return getNodeByKey<OutlineNode>(children[index - 1]);
   }
   getPreviousSiblings(): Array<OutlineNode> {
-    const parent = this.getParentOrThrow();
+    const parent = this.getParent();
+    if (parent === null) {
+      return [];
+    }
     const children = parent.__children;
     const index = children.indexOf(this.__key);
     return children
@@ -464,7 +470,10 @@ export class OutlineNode {
       .map((childKey) => getNodeByKeyOrThrow<OutlineNode>(childKey));
   }
   getNextSibling(): OutlineNode | null {
-    const parent = this.getParentOrThrow();
+    const parent = this.getParent();
+    if (parent === null) {
+      return null;
+    }
     const children = parent.__children;
     const childrenLength = children.length;
     const index = children.indexOf(this.__key);
@@ -474,7 +483,10 @@ export class OutlineNode {
     return getNodeByKey<OutlineNode>(children[index + 1]);
   }
   getNextSiblings(): Array<OutlineNode> {
-    const parent = this.getParentOrThrow();
+    const parent = this.getParent();
+    if (parent === null) {
+      return [];
+    }
     const children = parent.__children;
     const index = children.indexOf(this.__key);
     return children
diff --git a/packages/outline/src/core/OutlineRootNode.js b/packages/outline/src/core/OutlineRootNode.js
index 8a23c21ae..9d4952fe1 100644
--- a/packages/outline/src/core/OutlineRootNode.js
+++ b/packages/outline/src/core/OutlineRootNode.js
@@ -43,6 +43,12 @@ export class RootNode extends BlockNode {
     // You can't select root nodes.
     invariant(false, 'replace: cannot be called on root nodes');
   }
+  insertBefore() {
+    invariant(false, 'insertBefore: cannot be called on root nodes');
+  }
+  insertAfter() {
+    invariant(false, 'insertAfter: cannot be called on root nodes');
+  }
 
   // View
 
diff --git a/scripts/error-codes/codes.json b/scripts/error-codes/codes.json
index cc1f525b4..193496bc6 100644
--- a/scripts/error-codes/codes.json
+++ b/scripts/error-codes/codes.json
@@ -35,5 +35,7 @@
   "33": "createNode: node does not exist in nodeMap",
   "34": "reconcileNode: prevNode or nextNode does not exist in nodeMap",
   "35": "reconcileNode: parentDOM is null",
-  "36": "Reconciliation: could not find DOM element for node key \"${key}\""
+  "36": "Reconciliation: could not find DOM element for node key \"${key}\"",
+  "37": "insertBefore: cannot be called on root nodes",
+  "38": "insertAfter: cannot be called on root nodes"
 }