Rosalind Franklin is famous among scientists for her part in the discovery of the structure of DNA, an event that has revolutionised modern biological science. Her sister, writer and historian Jenifer Glyn, takes a full look at Rosalind’s life and shows how much she achieved and how she was influenced by the social and intellectual climate of her time. Here she discusses her sister with critic and Rosalind Franklin biographer Brenda Maddox.