Pets

and when they reject a kitten, there's usually a good reason that kitten won't survive the tough life of a feral. They concentrate their own limited energy on the kittens they know will survive.

The problems might be reversible or so minor a doting human wouldn't notice them, but they're there.

Tudor might just be adventurous, wanting to explore the world but too stupid to come in out of the rain. That would do it for momcat.