Index: sys/kern/subr_bus.c
===================================================================
--- sys/kern/subr_bus.c
+++ sys/kern/subr_bus.c
@@ -1928,6 +1928,45 @@
 	return (child);
 }
 
+static int
+device_detach_family(device_t dev)
+{
+	device_t child;
+	int error;
+
+	PDEBUG(("%s", DEVICENAME(dev)));
+
+	/* detach children first */
+	TAILQ_FOREACH(child, &dev->children, link) {
+		error = device_detach_family(child);
+		if (error)
+			goto done;
+	}
+	error = device_detach(dev);
+done:
+	return (error);
+}
+
+static void
+device_delete_family(device_t parent, device_t dev)
+{
+	device_t child;
+
+	PDEBUG(("%s from %s", DEVICENAME(dev), DEVICENAME(parent)));
+
+	/* delete children first */
+	while ((child = TAILQ_FIRST(&dev->children)) != NULL)
+		device_delete_family(dev, child);
+
+	if (dev->devclass)
+		devclass_delete_device(dev->devclass, dev);
+	if (dev->parent)
+		BUS_CHILD_DELETED(parent, dev);
+	TAILQ_REMOVE(&parent->children, dev, link);
+	TAILQ_REMOVE(&bus_data_devices, dev, devlink);
+	kobj_delete((kobj_t) dev, M_BUS);
+}
+
 /**
  * @brief Delete a device
  *
@@ -1945,28 +1984,16 @@
 device_delete_child(device_t dev, device_t child)
 {
 	int error;
-	device_t grandchild;
 
 	PDEBUG(("%s from %s", DEVICENAME(child), DEVICENAME(dev)));
 
-	/* remove children first */
-	while ((grandchild = TAILQ_FIRST(&child->children)) != NULL) {
-		error = device_delete_child(child, grandchild);
-		if (error)
-			return (error);
-	}
-
-	if ((error = device_detach(child)) != 0)
+	error = device_detach_family(child);
+	if (error)
 		return (error);
-	if (child->devclass)
-		devclass_delete_device(child->devclass, child);
-	if (child->parent)
-		BUS_CHILD_DELETED(dev, child);
-	TAILQ_REMOVE(&dev->children, child, link);
-	TAILQ_REMOVE(&bus_data_devices, child, devlink);
-	kobj_delete((kobj_t) child, M_BUS);
 
+	device_delete_family(dev, child);
 	bus_data_generation_update();
+
 	return (0);
 }