Ann Morgan Guilbert, sometimes credited as Ann Guilbert, was an American television and film actress and comedian who portrayed a number of roles from the 1950s on, most notably as Millie Helper in 61 episodes of the early 1960s sitcom The Dick Van Dyke Show, and later Yetta Rosenberg, Fran Fine's doddering grandmother, in 56 episodes of the 1990s sitcom The Nanny. Wikipedia