Britney Spears is on vacation in Hawaii with her two boys Sean Preston and Jayden James and fiancé Jason Trawick. The actress showed her rock-hard abs and toned frame are back in a new photo she posted on her Twitter account.  “Getting ready for some pool time! Having a blast xxoo,” the 30-year-old pop star wrote. The day before, she posted a pic of herself with the boys and Jason from their hotel in Maui, Hawaii.