I don't know where else to ask this question. The neighbour living a couple of doors down from an acquaintence cleaned out the garage at the back of his house and it was full of mice. These mice, looking for another place, found a hole under a sidewalk and gained access to this person's house. She has humanely trapped them and released them but this has been going on for two months and she's certain that they're coming in somewhere else. She has gone all around her house and can't find any way they could come in. How small a hole do they need? Someone said 1/4 inch if they'e young .Do they climb on roofs and go down chimneys? She doesn't want to kill them and asked if I knew of any way to repel them so they wouldn't want to come in to her house . ( It appears they're above the ceiling tile in the basement). I said I didn't but I'd ask. Any ideas?