my childs mother changed my kids last names with out me knowing.

  In order to change a child's surname, both parents must consent to same.  You should have been personally served with the petition for name change by a process server.  If a process server filed a return of service on you, and no answer was filed by you, then the court would enter the name change.   However, if you truly were not served, you can file a Motion to Set Aside the Judgment on the basis that you did not have true notice as required by law. This would have to be filed in the Court where the judgment was entered, and you would have to find out the procedure to set such a hearing before  the judge who heard the name change petition.    You can view the court file and see what the process server's return of service says as to who was served and when.   Good luck, Cindy Vova Law Office of Cindy S. Vova, P.A. 8551 West Sunrise Blvd., Suite 301 Plantation, FL 33322 info@vovalaw.com 954-316-3496