I am not sure if it is normal behavior for my MaMa cat to be handling her kittens very harshly when they get out of the the basket they have been staying in since birth. They are 3 weeks old and just starting to explore outside the basket on their own, when she sees that they are out she attacks them, bitting on the necks and kicking them. They do not cry so I am not sure if she is even hurting them, however it looks very rough and vicious. Is this normal behavior? Other than this she is a very attentive mom. Please let me know because I am worried that when I am not around she may hurt them.