colliders in children

Hi All

Say I have a game object with a rigifbody component and children (Transforms) each with a collider. Do I have to add rigidbody component on each child or the rigid body at the root is enough?

Because I have main character and child with box collider and only if I add rigidbody to the child my OnTriggerEnter is being called. But what if in the future I’ll have other children with collider on them?

Thank u in advance

You only need to attach a rigid body to the parent object and all child colliders are picked up by the parent object in a script attached to it. Have a look at the docs for compound colliders:
http://docs.unity3d.com/Documentation/Manual/Physics.html