Just Go with It (2011)

"Sometimes you need a girl, to get the girl."

While romancing Palmer, a much younger schoolteacher, plastic surgeon Danny Maccabee enlists his loyal assistant Katherine to pretend to be his soon to be ex-wife, in order to cover up a careless lie. When more lies backfire, Katherine's kids become involved, and everyone heads off for a weekend in Hawaii that will change all their lives.