 The theme song is "Let's Keep What We've Got," written by Hal David and performed by Marilyn McCoo.It appears in the opening credits while clips from the original "The Parent Trap" movie play, and is reprised in the closing credits when the final scene (Nicki and Mary, as junior bridesmaids/flower girls, walk up the aisle after their parents' wedding) is frozen.Other songs in the film include "Nothin' At All," sung by Andrea Robinson, who would later voice Ariel's mother, Athena, in Disney's "", and "Stand Back," sung by Stephanie Mills.