Legal Question in Family Law in California

You have a difficult path ahead, but one that is pretty legally simple. The law is very clear that the state of a child's primary residence for the last six months retains jurisdiction over custody of the child. So as long as you act before six months from when she left, California has jurisdiction over the children. You are going to have to file a case for a paternity judgment (which will be automatic if you did the proper paperwork when each child was born; you may have to prove paternity if it was not), and then for child custody and support orders and judgment. Once paternity is established, the case will proceed basically identically to a custody dispute in a divorce. The rights and court proceedings are the same. In that proceeding you can obtain a court order that the children be returned to California pending a final custody, visitation and support ruling. You will then have to request the AZ courts to recognize the CA order (which requires proper paperwork but is pretty much automatically granted). The AZ authorities will then enforce the order, up to and including law enforcement officers taking the children from her and returning them to CA if it goes that far. After that, it will be you and her duking it out in court the same as divorcing parents over custody, support and visitation, including whether they will live in CA or AZ. You have the upper hand in that, but there are no guarantees. The court must determine what is in the best interests of the children. As I hope you can readily see, this is not a place for self-help. You need a lawyer ASAP.