Trust me you run that very risk if you poison any rodents that might be able to gain entry to your house and you will then need to pay big bucks (and vacate for a while) to get rid. This would be AFTER your family have suffered flea bites galore.

Block entry points, buy a couple of wire traps & an ultra violet lamp to find pee drops and locate the trap there. No need to kill them at all, so please dont.

Just take them out to the country somewhere and set them loose but shut the car doors first.

Far easier and kinder to remove them. Good luck.