TV Land and Nick at Nite will pay tribute to John Ritter with two programming specials airing Sunday and Monday. The TV Land salute — which kicks off Sunday at 9 am/ET and lasts through the evening — will showcase Ritter's work on such sitcoms as The Mary Tyler Moore Show, The Cosby Show, Rhoda, Starsky & Hutch, The Waltons and The Bob Newhart Show. Nick at Nite, meanwhile, will air a Three's Company marathon beginning Monday at 9 pm/ET and continuing through Tuesday at 6 am/ET.