I am also seeing this gimpy fox in the yard from time to time he’s really growing thick fur. Tiger came up after I saw the fox and he ate very well. Glad to hear your babies are OK outside

Where do they shelter at night?

One, for sure, beneath their deck. I also see them in front of the house, running beneath the overgrown shrubs/evergreens.

They don't want the cats there but don't do anything to discourage them. That's why I keep trying to lure them to move to my property. Of course, I keep my greenery trimmed and deck maintained so I guess there's no real incentive. I've got 3 little temporary shelters for them that they do use, during the daytime. Spooky kept her kittens in one of them. That's where I suspect Arthur and his siblings were born because they were obviously newborns when I first saw them. 3 weeks later I rushed them to the vet because they had eye infections. That was the end of their feral life.