my dogs sleep in bed with me sometimes and my parents most of the time (they have a bigger bed than me.. I have a twin and they have a king)
and they don't have seperation anxiety or anything. or any dominance issues whatsoever, although my hound Buster thinks he can only sleep in bed with my parents and not the others. but he lets the other dogs on there most of the time.
and my cats sleep with me all the time since they can fit.