Christine Pullein-Thompson was the daughter of writer Joanna Cannan and Captain Harold "Cappy" Pullein-Thompson. She was part of a large literary family that included her maternal aunt May Cannan, a poet, and cousin Gilbert Cannan, a novelist-playwright. She and her three siblings all became writers. Along with her twin Diana Pullein-Thompson and other sister Josephine Pullein-Thompson, she was the author of many horse and pony books aimed mostly at girls, a genre established by their mother in the 1930s, which sold millions of copies. Christine also wrote a number of stories for younger children. The sisters also wrote a collective autobiography, Fair Girls and Grey Horses: Memories of Country Childhood. Christine married Julian Popescu in 1954 and had four children, one of whom, Charlotte Popescu, also wrote children's pony books.