Bristol Palin pregnant with third child

Bristol Palin is pregnant with her third child, she announced Friday on Entertainment Tonight.The daughter of former Alaska Gov. Sarah Palin, Palin, 26, is already mother to Tripp, 7, with her ex-boyfriend, Levi Johnston, and Sailor Grace, 1, with husband Dakota Meyer. She and Meyer, a National Medal of Honor winner, announced their marriage in June. In 2008, Palin made national headlines when she announced she was pregnant shortly after Republican presidential candidate John McCain picked her m