Sofia and her siblings, Jesus, Jose, and Maria, were last seen in Denver, Colorado on November 20, 2006. They have have never been heard from again. They are believed to have been abducted by their non-custodial father. Photographs and information about the father are unavailable. The Vizcaino Maldonado children may be in Mexico. Their mother has applied for their return to the United States under the terms of an international civil treaty: the Hague Convention on the Civil Aspects of International Child Abduction. The children has not been recovered as yet, however, and their cases remains unsolved.