She quit school after the eighth grade and toured the country with her family, often doing her elder sisters' make-up and occasionally singing backup.
Her role, as bombshell secretary Doralee Rhodes, had been originated by her older sister, Dolly Parton, in the hit 1980 theatrical film of the same name.
Sally Struthers joined the cast, and the sitcom's popularity revived, producing another 52 episodes before ending in 1988.
Dennison's last appearance on camera was during an episode of Bravo Profiles titled "Dolly Parton: Diamond in a Rhinestone World" in 1999.
Parton-George and her sister Dolly co-wrote Good Lookin' Cookin', a cookbook based on the Parton family upbringing; the book was released in 2024.