Dancing with the Stars' Melora Hardin has revealed that she will not only be dancing to the Disney song Mother Knows Best in week four - she will also be singing the track.MORE: Amanda Kloots makes bold comment about shock DWTS elimination of Christine ChiuThe Bold Type actress - who has performed on Broadway - will pre-record the song ahead of Tuesday's live show where she will dance with professional partner Artem Chigvintsev.WATCH: Dancing With The Stars: Melora Hardin's Cha Cha"For my