Thibooms

Say you have existing animation, but it's all sprite animated, no bones used. How to add bones for controlling that existing animation? The reason I am asking is that I want to copy/paste limbs, but in the tutorials I have seen you have to attach the limb sprites to bones (and then copy/paste to all frames) Edit: While I'm at it, how do you copy the animation from different entities over to other entities? I want to attach an arm from one entity to another (note: they use different sprites). I already have the different entities with their own animations in one same spriter project Thanks in advance