I think it's not possible, but wondering...if I make an animation in an assembly, call it a1, then I bring that assembly into another assembly, a2, and do an animation in a2, can I activate or use the animation already in a1 in cooperation with the animation in a2, or do I need to do all of the animation in one motion study in one assembly?  It would be nice if I could nest assembly motions like that, since I'll use the same subassembly in various assemblies, and it will be using similar motions.