Katherine de Roet Swynford, 18th GGM, Katherine married Hugh Swynford, a knight. Katherine became governess to the daughters of John of Gaunt. Katherine's sister, Philippa, married the poet Geoffrey Chaucer. After Blanche's death, Katherine and John of Gaunt consummated an affair which would entail four children being born to the couple, and would endure as a lifelong relationship. 2 years after the death of the Duke's second wife, Constance of Castile, Katherine and John married.