Career
She competed at the 1964 Summer Olympics in the 4×100 m medley relay and the 100 m backstroke and finished fifth and sixth, respectively. She finished third in the 1962 British Broadcasting Corporation Sports Personality of the Year. She held seven world records.
She retired from swimming in 1967.
Ludgrove was born to William and Gladys Ludgrove. She has a brother, Terence.
After marriage she changed her last name to Lillo.