diff --git a/src/threading/MsgThread.cc b/src/threading/MsgThread.cc
index dc399020da..7d7ab73a50 100644
--- a/src/threading/MsgThread.cc
+++ b/src/threading/MsgThread.cc
@@ -176,6 +176,7 @@ MsgThread::MsgThread() : BasicThread(), queue_in(this, 0), queue_out(0, this)
 	cnt_sent_in = cnt_sent_out = 0;
 	main_finished = false;
 	child_finished = false;
+	child_sent_finish = false;
 	failed = false;
 	thread_mgr->AddMsgThread(this);
 	}
@@ -185,9 +186,10 @@ extern int signal_val;
 
 void MsgThread::OnSignalStop()
 	{
-	if ( main_finished || Killed() )
+	if ( main_finished || Killed() || child_sent_finish )
 		return;
 
+	child_sent_finish = true;
 	// Signal thread to terminate.
 	SendIn(new FinishMessage(this, network_time), true);
 	}
diff --git a/src/threading/MsgThread.h b/src/threading/MsgThread.h
index 70d6fafc6e..1f5ec0e017 100644
--- a/src/threading/MsgThread.h
+++ b/src/threading/MsgThread.h
@@ -306,6 +306,7 @@ private:
 
 	bool main_finished;	// Main thread is finished, meaning child_finished propagated back through message queue.
 	bool child_finished;	// Child thread is finished.
+	bool child_sent_finish; // Child thread asked to be finished.
 	bool failed;	// Set to true when a command failed.
 };