How to change one child object to another with the same armature?

I've got a problem with my playermodel. My playermodel have got armature with animation and that armature is attached to it's mesh. But mesh is divided into smaller child meshes like this: How can I change these child objects to another child objects (for example customizable tail) if I've got my new gameobject (of tail) with the same armature? How to attach gameobjects to armature that have animation?