This Sept. 3, 2008 file photo shows Bristol Palin and her boyfriend Levi Johnston at the Republican National Convention in St. Paul, Minn. (AP)
In this July 25, 2009, photo, Bristol Palin holds her and Levi Johnston's son Tripp Johnston at the governor's picnic in Anchorage, Alaska. (AP)
"Dancing with the Stars" finalists, Bristol Palin, right, and Mark Ballas appear on ABC's "Good Morning America" in New York, Wednesday, Nov. 24, 2010. (AP)
Bristol Palin signs her new book at the Mall of America Wednesday, June 29, 2011 in Bloomington, Minn. (AP)
Bristol Palin and Melissa Rycroft attend the "Dancing with the Stars: All Stars" panel at the Beverly Hilton Hotel on Friday, July 27, 2012, in Beverly Hills, Calif. (AP)
McKinley Wooten, Bristol Palin, and Piper Palin arrive at the Just Dance 4 launch on Tuesday, Oct. 2, 2012 in Los Angeles (AP)