A father has the right to know where his children live in almost all cases. The only time a father would not have this right is if the child's mother has been granted sole legal and physical custody of the child by a court. In these cases, the father would need to get permission from the court before he could learn the child's whereabouts. However, even in these situations, there are usually ways for the father to find out where his children are living if he is truly determined to do so.