Why is my dog so jealous and mean

I have 3 dogs. Jazzy who is the oldest Katniss is Jazzy's daughter and Laya who is about to turn 3.She is the problem child she is the littlest she is a. toy poodle mix and she is very loud and demanding she always wants my attention when I don't give it to her she misbehaves like barking at the TV for no reason or being unreasonably violent to Jazzy and Katniss she snaps at them and bites at their chins a whole lot.She has possessive qualities and has hard time sharing me with other dogs. Why is she so jealous do you guys have this problem I need advice please.