I started out a year ago fostering a mom and her kitten, well when it came time to put them up for adoption, I adopted them both. Mom and son. The son has become very aggressive. He just tackled Mom and pushed her down the stairs, and had her pinned on her back, while he was on her stomach biting her. I stamped my foot and clapped my hands and he let go an ran. I have always had cats, just never more than one at a time. Is this normal behavior for several cats? What can I do to stop it? Mom is a sweet calico and son looks like a Bombay, looks like a panther, really long and big. Bigger than Mom. Someone please help.