No mice here - but my wife discovered baby rabbits in the front yard. The mother had dug a hole by the sidewalk for herself and one for the babies about three feet away.
Did I mention we have a dog? That sits on the front porch a lot? This rabbit dropped her babies well within the dog zone. Lucky for them the dog is terrified of anything that moves.
But I did go out and buy tomato cages - both to keep any delivery guys from stepping in the hole and to keep the dog away from the babies.
Mama moved out of her hole about two-three days after we discovered them (and that hole got filled right after), but the babies didn't leave until a couple days ago. It was kind of cool watching them grow from little pink balls of not much into little furry balls with no real fear of humans to actual rabbits with rabbit sense. On one of the first days out of the hole, I could hear the dog barking, then this high-pitched wailing - turns out the dog scared one and it ran screaming across the steps. About three days later, the frigging dog walked past one of the babies. At least three times. We're talking less than a foot away. That dog would not survive in the wild, not at all.