I have 6 week old kittens, mom is a stray I had been feeding. I let her inside during a cold spell and she gave birth to 2 kittens. I have kept mom inside with her kittens but she is starting to crave the outdoors. One kitten has been peeing in the litter box for a week and just yesterday took her first poo in the litter box. This kitten will also drink water and KRM. The other kitten is still not using the bathroom on her own and shows no interest in anything except milk straight from mom. I don't know if I am worrying for no reason? Mom is still very attached to this kitten especially. How can I get this kitten to be more independent? Or do kittens sometime develop at different speeds?