kitten and cat

Hi,
I have a problem. i got a kitten about two weeks ago.His name is socks.and I already have a cat named Birdie. she is about three years old and he is eight weeks old. They both are friends now.they lay by each other.But this morning socks was playing with her toy.And birdie jumped on him and started kicking him like she was playing with him.Is that normal? Is she showing who is boss? or just playing with him? she is always nice.
Thank you reading my quistion.

She is probably just playing...as long as the little one is not getting hurt, I think it should be okay.

Thats how the big cat teaches the little one how to fight. its normal.

Thanks!!!!!!!!!! I got scared.....Thanks.