Visit the official site: Watch Tammy Cartwright sing One Night Only by Jennifer Hudson Brace yourself for a doublewhammy of Tammy Not only do we bear witness to Tammy s powerhouse performance, but we also get to meet her nutty nan, May. Watch as May storms the stage to support her granddaughter, scoring herself some smiles off Mel B AND a hug from Dermot. Atta girl br, br,