Sally Thomsett (born 3 April 1950)[1] is an English actress who starred as Phyllis in the film The Railway Children (1970) and played Jo in the TV sitcom Man About the House (1973–1976).
Thomsett was contractually forbidden to reveal her age during production, and was likewise not allowed to smoke, drink, drive a car, or be seen in public with her boyfriend.
[6][7] The film crew were unaware of her true age, and treated her as they would a child (e.g. by giving her sweets), while addressing the younger Agutter as they would an adult.
[8] During an appearance shortly afterwards on a BBC children's television programme, Thomsett was told, "I wouldn't dream of asking a lady her age, but you're obviously quite a bit older than the part you played in the film".
After appearing in a television commercial advertising Bovril in 1972, Thomsett was spotted by writers Brian Cooke and Johnnie Mortimer, who cast her in the hit ITV sitcom Man About the House as Jo, a role that she played for the show's entire run from 1973 to 1976, including a 1974 spin-off film of the same name.