At just over 15-years-of-age, Lillian Birkenhead was the youngest member of the Great Britain swimming squad at the 1920 Antwerpen Olympics. Not only was she a member of the famous Garston Swimming Club, but she also attended the Garston Church of England school, which also nurtured fellow Olympians Charlotte Radcliffe, Grace McKenzie and James Worthington. When she was 12, Birkenhead won the 50 yards schoolgirls championship at the 1917 Garston Baths Gala. Within two years, she had won both the Liverpool and Merseyside schools freestyle titles, and in 1919 took part in the 100 free at the ASA Championship at her home baths when she was just 14. Despite not enjoying an ASA podium finish, Birkenhead qualified for the 1920 Olympics after winning her heat in the final trials at nearby Southport. She got married at the age of 18 and started a family, thus bringing an end to her competitive swimming career.