Cooper is strong enough to sit and play in the saucer. I think he is doing physical things sooner than Cadence was. He really likes to sit up and has such strong stomach muscles! (Not quite a six-pack though).
Cadence decided that she can't be outdone by his strength. I believe she was sad that she didn't let me paint her face for the Halloween party. Therefore, she painted it by herself! And had fun doing it!!!