Caroline Gilchrist Rhea (born April 13, 1964) is a Canadian actress, TV personality, host, and stand-up comedienne. She is also known for her role as Hilda Spellman on Sabrina, the Teenage Witch, and for replacing Rosie O'Donnell as the hostess of her syndicated talk show, renamed The Caroline Rhea Show. She was the original host of the reality television show The Biggest Loser on NBC, until Alison Sweeney took her place after the end of the third season.She provides the voice for Linda Flynn, mother of Phineas and Candace Flynn, on the Disney Channel series Phineas and Ferb. She would return to Disney Channel on the series Sydney to the Max, playing the role of Grandma Judy.She has performed numerous comedy specials, including three one-hour standup specials for HBO, Showtime, and Bravo.