Joan Procter, CP's younger sister was born in London on 5 August 1897. She was fragile from birth and her schooling at St Paul's Girls' School was much interrupted by illness, although she was recognised as a brilliant student. Her precarious health meant that she had to give up her intention of going to Cambridge to study but she was able to follow her academic interest in zoology when she went to assist George A Boulenger, Keeper of Reptiles and Fishes at the British Museum in 1917. She had first impressed Boulenger with enquiries about identification of specimens as a child when her intense interest in reptiles led to her taming and keeping a number of species as pets, in particular a large Dalmation lizard which travelled everywhere with her and sat on the table beside her at meals. In August 1917, JP was elected a Fellow of the Zoological Society and from then until her death she continued scientific research, publishing widely and becoming internationally recognised as a leading herpetologist. When G A Boulenger retired in 1920, JP was in sole charge of reptiles at the British Museum. In 1923, she was asked to assist Mr Edward Boulenger in the design and construction of the rockwork and backgrounds for tanks in the new Aquarium at London Zoo and she was appointed Curator of Reptiles the same year. She became an expert surgeon and had great success in taming many different species. She was responsible for the design and construction of a new Reptile House at the Zoo, a new Main Gate, Reptiliary, and Baboons' Enclosure. She also took an active interest in Whipsnade. All this was accomplished against the background of constant pain and chronic ill-health with great determination and good humour. She died on 20 September 1931, aged thirty-four.