Jimmie Allen used a comical montage of movie and TV clips to announce that he’s going to be a dad to a 3rd child! Jimmie and his wife, Alexis, are already parents to their year-and-a-half-old daughter Nomi Bettie, and 7-year-old song Aadyn, who is Jimmie’s son from a previous relationship. Alexis shared a series of…