First off: I created this little Bendy Bone and want it to move with the arm. So i parented it to the Arm with automatic weights. This happened:
Only the inner part moves. This makes no sense since the whole arm is ONE Object. Heres a more detailed view:
It may be because the arm Object consisted of two Objects before that I just joined together, but i dont want to remodel it, unless there is no way around it.
Help is much appreciated.