Pullein-Thompson was born on 3 April 1924 into a notable family. Her father, Harold Pullein-Thompson, had won the
Military Cross and her mother,
Joanna Cannan, was a prolific and successful author. She was the second child, as she had an elder brother who would adopt his mother's name to be a successful playwright of comedies as
Denis Cannan. She also had two younger sisters (who were twins), and all the children would be writers. The family home was a villa in the suburb of
Wimbledon, where her father would have two seats on the centre court. Her father was badly wounded and in frequent pain; he had earned the
Military Cross during the war. He had been a teacher before the war but he sold fridges and had a game company. The girls had an unusual education, as distinct from their brother who went to
Eton College. She was taught by a "mad woman in a hut" and she was rebellious and stubborn. The girls prided themselves on not conforming to expectations. The riding school brought in extra money as the three sisters taught others to ride. In 1946, she had her first book,
Six Ponies, published. She had also helped write
It Began With Picotee, which the three sisters created together in 1941, but published also in 1946. The sisters would write dozens of books and Josephine wrote four dozen herself. Josephine was vice president of the Woodland Hunt Branch of the British
Pony Club. ==Private life==