She competed in the County Championships of 1907 with three of her sisters, Alice, Kathleen and Sibyl, helping Durham to defeat Middlesex 5–4. Aitchison entered the Wimbledon Championships for the first time in 1909, at the age of 27, winning the Ladies Doubles title with partner Agnes Tuckey. She also competed in 1910, 1911, 1913 and 1914, reaching three semi-finals and two quarter-finals in the Ladies Singles. In 1913 she won the singles title at World Covered Court Championship in Stockholm, defeating Kate Gillou in the final in straight sets. Her success at the Stockholm Olympics in 1912 made her the first person from Sunderland to become an Olympic medalist.
He competed in the County Championships of 1907 with three of his sisters, Alice, Kathleen and Sibyl, helping Durham to defeat Middlesex 5-4. Aitchison entered the Wimbledon Championships for the first time in 1909, at the age of 27, winning the Ladies Doubles title with partner Agnes Tuckey. He also competed in 1910, 1911, 1913 and 1914, reaching three semi-finals and two quarter-finals in the Ladies Singles. In 1913 he won the singles title at World Covered Court Championship in Stockholm, defeating Kate Gillou in the final in straight sets. His success at the Stockholm Olympics in 1912 made him the first person from Sunderland to become an Olympic medalist.