Oscar, Tony and Emmy winning actor, Maggie Smith, best known for playing Professor McGonagall in the “Harry Potter” movie franchise and the dowager Countess of Grantham on “Downton Abbey,” died Friday at the age of 89. Smith’s sons, Chris Larkin and Toby Stephens, paid tribute to their mother in a joint statement. “It is with great sadness we have to announce the death of Dame Maggie Smith. She passed away peacefully in hospital early this morning,” they wrote.