diff --git a/CHANGELOG.md b/CHANGELOG.md
index 067d04f2b2..97cea44031 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -64,6 +64,7 @@ Docs: https://docs.openclaw.ai
 - CLI/Configure: make the `/model picker` allowlist prompt searchable with tokenized matching in `openclaw configure` so users can filter huge model lists by typing terms like `gpt-5.2 openai/`. (#19010) Thanks @bjesuiter.
 - Voice Call: add an optional stale call reaper (`staleCallReaperSeconds`) to end stuck calls when enabled. (#18437)
 - Auto-reply/Subagents: propagate group context (`groupId`, `groupChannel`, `space`) when spawning via `/subagents spawn`, matching tool-triggered subagent spawn behavior.
+- Subagents: route nested announce results back to the parent session after the parent run ends, falling back only when the parent session is deleted. (#18043)
 - Subagents: cap announce retry loops with max attempts and expiry to prevent infinite retry spam after deferred announces. (#18444)
 - Agents/Tools/exec: add a preflight guard that detects likely shell env var injection (e.g. `$DM_JSON`, `$TMPDIR`) in Python/Node scripts before execution, preventing recurring cron failures and wasted tokens when models emit mixed shell+language source. (#12836)
 - Agents/Tools/exec: treat normal non-zero exit codes as completed and append the exit code to tool output to avoid false tool-failure warnings. (#18425)
diff --git a/extensions/voice-call/src/cli.ts b/extensions/voice-call/src/cli.ts
index 963fa6f517..eaf4e3fc0a 100644
--- a/extensions/voice-call/src/cli.ts
+++ b/extensions/voice-call/src/cli.ts
@@ -62,8 +62,14 @@ function summarizeSeries(values: number[]): {
     return { count: 0, minMs: 0, maxMs: 0, avgMs: 0, p50Ms: 0, p95Ms: 0 };
   }
 
-  const minMs = values.reduce((min, value) => (value < min ? value : min), Number.POSITIVE_INFINITY);
-  const maxMs = values.reduce((max, value) => (value > max ? value : max), Number.NEGATIVE_INFINITY);
+  const minMs = values.reduce(
+    (min, value) => (value < min ? value : min),
+    Number.POSITIVE_INFINITY,
+  );
+  const maxMs = values.reduce(
+    (max, value) => (value > max ? value : max),
+    Number.NEGATIVE_INFINITY,
+  );
   const avgMs = values.reduce((sum, value) => sum + value, 0) / values.length;
   return {
     count: values.length,
diff --git a/src/agents/subagent-announce.format.e2e.test.ts b/src/agents/subagent-announce.format.e2e.test.ts
index e77c7c81de..44c7c2cc27 100644
--- a/src/agents/subagent-announce.format.e2e.test.ts
+++ b/src/agents/subagent-announce.format.e2e.test.ts
@@ -838,4 +838,48 @@ describe("subagent announce formatting", () => {
     expect(call?.params?.deliver).toBe(true);
     expect(call?.params?.channel).toBe("discord");
   });
+
+  it("falls back when parent session is missing a sessionId (#18037)", async () => {
+    const { runSubagentAnnounceFlow } = await import("./subagent-announce.js");
+    embeddedRunMock.isEmbeddedPiRunActive.mockReturnValue(false);
+    embeddedRunMock.isEmbeddedPiRunStreaming.mockReturnValue(false);
+
+    subagentRegistryMock.isSubagentSessionRunActive.mockReturnValue(false);
+    sessionStore = {
+      "agent:main:subagent:newton": {
+        sessionId: " ",
+        inputTokens: 100,
+        outputTokens: 50,
+      },
+      "agent:main:subagent:newton:subagent:birdie": {
+        sessionId: "birdie-session-id",
+        inputTokens: 20,
+        outputTokens: 10,
+      },
+    };
+    subagentRegistryMock.resolveRequesterForChildSession.mockReturnValue({
+      requesterSessionKey: "agent:main:main",
+      requesterOrigin: { channel: "discord" },
+    });
+
+    const didAnnounce = await runSubagentAnnounceFlow({
+      childSessionKey: "agent:main:subagent:newton:subagent:birdie",
+      childRunId: "run-birdie-empty-parent",
+      requesterSessionKey: "agent:main:subagent:newton",
+      requesterDisplayKey: "subagent:newton",
+      task: "QA task",
+      timeoutMs: 1000,
+      cleanup: "keep",
+      waitForCompletion: false,
+      startedAt: 10,
+      endedAt: 20,
+      outcome: { status: "ok" },
+    });
+
+    expect(didAnnounce).toBe(true);
+    const call = agentSpy.mock.calls[0]?.[0] as { params?: Record<string, unknown> };
+    expect(call?.params?.sessionKey).toBe("agent:main:main");
+    expect(call?.params?.deliver).toBe(true);
+    expect(call?.params?.channel).toBe("discord");
+  });
 });
diff --git a/src/gateway/server-node-events.test.ts b/src/gateway/server-node-events.test.ts
index 77530882e3..07525311a0 100644
--- a/src/gateway/server-node-events.test.ts
+++ b/src/gateway/server-node-events.test.ts
@@ -29,12 +29,12 @@ vi.mock("./session-utils.js", () => ({
 }));
 
 import type { CliDeps } from "../cli/deps.js";
-import type { HealthSummary } from "../commands/health.js";
-import type { NodeEventContext } from "./server-node-events-types.js";
 import { agentCommand } from "../commands/agent.js";
+import type { HealthSummary } from "../commands/health.js";
 import { updateSessionStore } from "../config/sessions.js";
 import { requestHeartbeatNow } from "../infra/heartbeat-wake.js";
 import { enqueueSystemEvent } from "../infra/system-events.js";
+import type { NodeEventContext } from "./server-node-events-types.js";
 import { handleNodeEvent } from "./server-node-events.js";
 
 const enqueueSystemEventMock = vi.mocked(enqueueSystemEvent);
diff --git a/src/gateway/server-node-events.ts b/src/gateway/server-node-events.ts
index bd662a126a..267d53f7ec 100644
--- a/src/gateway/server-node-events.ts
+++ b/src/gateway/server-node-events.ts
@@ -76,7 +76,10 @@ function shouldDropDuplicateVoiceTranscript(params: {
   ) {
     return true;
   }
-  recentVoiceTranscripts.set(params.sessionKey, { fingerprint: params.fingerprint, ts: params.now });
+  recentVoiceTranscripts.set(params.sessionKey, {
+    fingerprint: params.fingerprint,
+    ts: params.now,
+  });
 
   if (recentVoiceTranscripts.size > MAX_RECENT_VOICE_TRANSCRIPTS) {
     const cutoff = params.now - VOICE_TRANSCRIPT_DEDUPE_WINDOW_MS * 2;
diff --git a/src/plugins/voice-call.plugin.test.ts b/src/plugins/voice-call.plugin.test.ts
index a9c4c49b74..f978defe19 100644
--- a/src/plugins/voice-call.plugin.test.ts
+++ b/src/plugins/voice-call.plugin.test.ts
@@ -1,7 +1,7 @@
-import { Command } from "commander";
 import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
+import { Command } from "commander";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
 let runtimeStub: {