Look at this! You can get an excited baby chick to fall asleep by gently rubbing its belly. You wouldn’t believe how many different kinds of lizards I’ve tried this on, and it worked on all of them. Would it work on an adult chicken? Betcha it would.
Our cats, Robbie and Peep, like having their bellies rubbed, but it doesn’t put them to sleep. It would if they were lizards. But then they wouldn’t be nice and furry.