I moved them to a little bigger place. They can mill about, and travel clear over to me a half-meter away to nag for food. They’re aware of when they need to poop and may be able to keep it a little cleaner. I think they enjoy yelling; they definitely enjoy the bottle and cuddling afterwards. Cleanup is not so popular.
Pernicious drinks so fast and hard that he makes the bottle squeak. Last week, he’d kind of trip on it and end up sneezing milk out his nose. He’s better at it now and eats more than the others in less time.