The Hills Newlywed 'Hills' star Heidi Montag changes her name to Heidi Pratt 05/12/2009 Now that their marriage is officially official, Heidi Montag has formally taken Spencer Pratt's last name. Read More RELATED NEWS Kristin Cavallari debuts new 24-year-old boyfriend Mark EstesBrody Jenner and Tia Blanco welcome their first child'The Hills' alum Brody Jenner engaged to pregnant girlfriend Tiarah "Tia" Blanco TAGS: Heidi Montag
