“What? You’re petting someone else!? Human varlet! What were you thinking?”
My cats Buster and Missy used to fight over space on Daddy’s lap–they were too big for both of them to fit–but only seldom lapsed into spasms of real jealousy. Buster was one of those casual cats who always managed to get yelled at for doing something he shouldn’t. But, oh! how happy he was, whenever Missy got yelled at. He just about turned cartwheels.
Active jealousy, though? Nah–that’s just the cats in this video.