diff --git a/CHANGELOG.md b/CHANGELOG.md
index 160cbbd2e54..bbda027a48d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,7 +6,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
-- Control UI/sessions: nest subagent sessions under their parent session in the session picker dropdown using a visual `└─ ` prefix, making the parent-child relationship clear. Fixes #77628.
+- Control UI/sessions: nest subagent sessions under their parent session in the session picker dropdown using a visual `└─ ` prefix, making the parent-child relationship clear. Fixes #77628. (#78623) Thanks @chinar-amrutkar.
 
 ### Changes
 
diff --git a/ui/src/ui/app-render.helpers.node.test.ts b/ui/src/ui/app-render.helpers.node.test.ts
index 2fc934aa44a..3e55f629811 100644
--- a/ui/src/ui/app-render.helpers.node.test.ts
+++ b/ui/src/ui/app-render.helpers.node.test.ts
@@ -676,7 +676,23 @@ describe("resolveSessionOptionGroups", () => {
     });
 
     expect(labels).toContain("Spock");
-    expect(labels).toContain("└─ subagent:f4ac7ef1-1234-5678-9abc-def012345678");
+    expect(labels).toContain("└─ f4ac7ef1-1234-5678-9abc-def012345678");
+  });
+
+  it("preserves sibling row order when nesting subagent sessions", () => {
+    const parentKey = "agent:main:main";
+    const newerSubagentKey = "agent:main:subagent:newer";
+    const olderSubagentKey = "agent:main:subagent:older";
+    const labels = labelsForSessionOptions({
+      sessionKey: parentKey,
+      sessions: [
+        row({ key: newerSubagentKey, label: "Newer", spawnedBy: parentKey }),
+        row({ key: olderSubagentKey, label: "Older", spawnedBy: parentKey }),
+        row({ key: parentKey, label: "Spock" }),
+      ],
+    });
+
+    expect(labels).toEqual(["Spock", "└─ Newer", "└─ Older"]);
   });
 });
 
diff --git a/ui/src/ui/chat/session-controls.ts b/ui/src/ui/chat/session-controls.ts
index 8334ace6765..f0df9a8b1ed 100644
--- a/ui/src/ui/chat/session-controls.ts
+++ b/ui/src/ui/chat/session-controls.ts
@@ -731,16 +731,32 @@ export function resolveSessionOptionGroups(
 
   for (const group of groups.values()) {
     const options = group.options;
-    for (let i = options.length - 1; i >= 0; i--) {
-      const parentKey = options[i].parentKey;
-      if (parentKey) {
-        const parentIdx = options.findIndex((o) => o.key === parentKey);
-        if (parentIdx !== -1) {
-          const [child] = options.splice(i, 1);
-          options.splice(parentIdx + 1, 0, child);
+    const optionKeys = new Set(options.map((option) => option.key));
+    const childrenByParent = new Map<string, SessionOptionEntry[]>();
+    for (const option of options) {
+      if (option.parentKey && optionKeys.has(option.parentKey)) {
+        const siblings = childrenByParent.get(option.parentKey);
+        if (siblings) {
+          siblings.push(option);
+        } else {
+          childrenByParent.set(option.parentKey, [option]);
         }
       }
     }
+    if (childrenByParent.size > 0) {
+      const reordered: SessionOptionEntry[] = [];
+      for (const option of options) {
+        if (option.parentKey && optionKeys.has(option.parentKey)) {
+          continue;
+        }
+        reordered.push(option);
+        const children = childrenByParent.get(option.key);
+        if (children) {
+          reordered.push(...children);
+        }
+      }
+      options.splice(0, options.length, ...reordered);
+    }
   }
 
   for (const group of groups.values()) {