Normal Silkie chick behavior

This is my first time owning chickens & I was wondering if this was normal silkie chick behavior! There’s one chick that is always fighting the others & recently has been ganged up on. They accept him in the cuddle puddle at night but they’re squabbling often during the day. They always have fresh food & water & have a heating plate. I have a mirror & a perch in with them, could they be bored & need more stimulation?