Proud parents, Ashlee Simpson and Pete Wentz, threw a SpongeBob themed birthday party for son Bronx Mowgli.[caption id="attachment_64637" align="alignnone" width="259" caption=""][/caption]Bronx turned 1 on Friday, Novmeber 20th, but the party was held on Saturday at Joe and Tina Simpson's house in Encino, California. Guest were treated to a bounce house, cake and a surprise appearance from SpongeBob.Pete thanked party planner, Mindy Weiss, on his Twitter page for the "rad b-day for bronx."