diff --git a/tests/test_litellm/proxy/db/conftest.py b/tests/test_litellm/proxy/db/conftest.py
index 03d7ea81257..d3226b0ec50 100644
--- a/tests/test_litellm/proxy/db/conftest.py
+++ b/tests/test_litellm/proxy/db/conftest.py
@@ -6,7 +6,7 @@ import time
 from collections.abc import Generator
 from dataclasses import dataclass
 from pathlib import Path
-from typing import Optional
+from typing import Final, Optional
 
 import pytest
 
@@ -122,10 +122,18 @@ class FakePrismaCli:
         return [json.loads(line) for line in self.calls_file.read_text().splitlines()]
 
     def grandchild_is_gone(self, within_seconds: float) -> bool:
-        deadline = time.monotonic() + within_seconds
+        pid: Final = int(self.grandchild_pidfile.read_text())
+        deadline: Final = time.monotonic() + within_seconds
         while time.monotonic() < deadline:
+            if os.name != "nt":
+                try:
+                    reaped_pid, _ = os.waitpid(pid, os.WNOHANG)
+                    if reaped_pid == pid:
+                        return True
+                except ChildProcessError:
+                    pass
             try:
-                os.kill(int(self.grandchild_pidfile.read_text()), 0)
+                os.kill(pid, 0)
             except ProcessLookupError:
                 return True
             time.sleep(0.05)
@@ -154,3 +162,4 @@ def fake_prisma_cli(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Generato
             os.kill(int(cli.grandchild_pidfile.read_text()), signal.SIGKILL)
         except ProcessLookupError:
             pass
+        assert cli.grandchild_is_gone(within_seconds=5)
diff --git a/tests/test_litellm/proxy/db/test_query_engine_reaper.py b/tests/test_litellm/proxy/db/test_query_engine_reaper.py
index efcecb4bc08..5018176854e 100644
--- a/tests/test_litellm/proxy/db/test_query_engine_reaper.py
+++ b/tests/test_litellm/proxy/db/test_query_engine_reaper.py
@@ -3,6 +3,7 @@ import signal
 import subprocess
 import sys
 import time
+from typing import Final
 from unittest.mock import MagicMock, patch
 
 import pytest
@@ -15,7 +16,6 @@ from litellm.proxy.db.query_engine_reaper import (
     _try_reap,
     list_orphaned_engine_pids,
     reap_orphaned_engines,
-    set_child_subreaper,
     start_query_engine_reaper,
     terminate_and_reap,
     terminate_and_reap_all,
@@ -79,11 +79,19 @@ class TestListOrphanedEnginePids:
 
 class TestSetChildSubreaper:
     def test_matches_platform_capability(self):
-        result = set_child_subreaper()
-        if sys.platform.startswith("linux"):
-            assert result is True
-        else:
-            assert result is False
+        result: Final = subprocess.run(
+            [
+                sys.executable,
+                "-c",
+                "import sys; "
+                "from litellm.proxy.db.query_engine_reaper import set_child_subreaper; "
+                "assert set_child_subreaper() is sys.platform.startswith('linux')",
+            ],
+            capture_output=True,
+            text=True,
+            timeout=30,
+        )
+        assert result.returncode == 0, result.stderr
 
 
 @pytest.mark.skipif(sys.platform == "win32", reason="POSIX signals and waitpid")
diff --git a/tests/test_litellm/proxy/test_proxy_cli.py b/tests/test_litellm/proxy/test_proxy_cli.py
index 0c20d5e0ff0..c76ff189a8a 100644
--- a/tests/test_litellm/proxy/test_proxy_cli.py
+++ b/tests/test_litellm/proxy/test_proxy_cli.py
@@ -1525,7 +1525,12 @@ class TestProxyInitializationHelpers:
         def capture_run(self):
             captured["options"] = dict(self.options)
 
-        with patch("gunicorn.app.base.BaseApplication.run", capture_run):
+        with (
+            patch("gunicorn.app.base.BaseApplication.run", capture_run),
+            patch(  # test-quality-ok: option tests must not start a thread or change the pytest worker's child ownership
+                "litellm.proxy.proxy_cli.start_query_engine_reaper"
+            ),
+        ):
             ProxyInitializationHelpers._run_gunicorn_server(
                 host="127.0.0.1",
                 port=4010,
@@ -1553,6 +1558,9 @@ class TestProxyInitializationHelpers:
         with (
             patch("gunicorn.app.base.BaseApplication.run", capture_run),
             patch("builtins.print") as mock_print,
+            patch(  # test-quality-ok: option tests must not start a thread or change the pytest worker's child ownership
+                "litellm.proxy.proxy_cli.start_query_engine_reaper"
+            ),
         ):
             ProxyInitializationHelpers._run_gunicorn_server(
                 host="127.0.0.1",