Latin law expression for "father of his country," the term for the doctrine that the government is the ultimate guardian of all people under a disability, especially children, whose care is only "entrusted" to their parents. Under this doctrine, in a divorce action or a guardianship application the court retains jurisdiction until the child is 18 years old, and a judge may change custody, child support or other rulings affecting the child's well-being, no matter what the parents may have agreed or the court previously decided.