Rico and Rodriguez are the unmarried parents of two minor children: M.P., born March 26, 1993; and J.P., born April 25, 1995. Rico, M.P., and J.P. are citizens of Mexico. From 1996 to 2003, Rico maintained primary physical custody of the children. In 2003, Rico and the children illegally emigrated from Mexico to Las Vegas. After moving to Las Vegas, M.P. and J.P. telephoned Rodriguez to ask if they could live with him. That summer, Rodriguez filed a petition in district court for determination of paternity, custody, support, and visitation. At the time of the proceedings, Rodriguez was a citizen of Mexico with permanent legal residency in the United States and was living with his wife in the State of Washington.