Player prefab : sync child rigidbody

Hi everyone,

I started to implement the networking system in my project, but i don't know how i can handle child rigidbodies. The NetworkTransform component only manages the parent object of the prefab (i added a NetworkTransform on both childs it doesn't change anything, maybe the childs have to be spawned on the network too ?). Actually the 5.2 update adds a "NetworkTransformChild" component but only sync transform position and rotation, no physic.

Here is my prefab...

Player prefab : sync child rigidbody