Mary Lynn Sartori was born and raised in Glendale, California. She took dancing lessons from an early age, and at the time she joined the club, was hoping to become a choreographer. She listed her favorite activities as roller skating, horseback riding, and swimming, and collected dolls as a hobby. Before starting with the show she attended All Saints Catholic Grammar School.
Though only of average height, Mary reached her full growth at age twelve, and had started to develop a becoming figure. In the third season the show's producers would be quite comfortable with their female Mouseketeer's nascent sex appeal, but the first season director Dik Darley was a little unsure how to use Mary, or the similarly endowed Bonni Kern. Both girls really belonged on the Red Team and Roll Call, but instead both were sidelined on the Blue Team. Mary was not only a good dancer, she also had an engaging on-camera persona, as shown in her solo for I Wanna Be a Fireman.
The first season choreography emphasized group storylines rather than couples, but when needed, Mary was usually paired with Don Underhill
or Dennis Day
. In the latter half of that season's filming Mary was moved to the Red Team, probably after Nancy Abbate's
departure. At that point, Mary and Annette
were the only Italian-American girls left, so it was natural for them to become friends. Though she left the Mouseketeers in January 1956, Mary returned during the second season as a Talent Round-Up winner
, having finally found a dancing partner (John F. Smith) taller than her. While her partner was given the standard talent winner hats and song, Mary received a mortarboard hat with mouse ears while the Mouseketeers sang You're a Mousekegraduate
After leaving the show Mary attended Alhambra High School. She kept in touch with Annette, and took part in a couple of fan magazine photo layouts at Annette's house. She had a small recurring role in the TV series Sheriff of Cochise, a contemporary police drama set in Cochise County, Arizona. Mary graduated from high school in 1960, worked as a telephone operator, then attended Pasadena City College, where she joined Theta Gamma sorority. She left college after one year to marry Lee Celano, a wholesale meat dealer, on January 27, 1962. Mary then worked at Lockheed until the birth of her first son in 1964. A second son followed in 1966. Mary attended the 20th Anniversary events at Disneyland in 1975, and took part in the televised 1980 reunion show.