Kitson's cousin, Edith Cliff, was the Commandant and his daughter Doris and her cousin Olive Middleton were  VAD nurses.
The passage describes the familial connections of Kitson, with his cousin Edith Cliff holding a leadership role as Commandant. His daughter Doris and her cousin Olive Middleton were also nurses, likely part of the Voluntary Aid Detachment (VAD) during that time.