Guinevere is childless in most stories, In Alliterative Morte Arthure, Guinevere willingly becomes Mordred's consort and bears him two sons, though this is implied rather than stated in the text.There were mentions of Arthur's sons in the Welsh Triads, though their exact parentage is not clear. A half-sister and a brother play the antagonists in the Lancelot–Grail and the German romance Diu Crône respectively, but neither character is mentioned elsewhere.The Welsh poet Dafydd ap Gwilym alludes to Guinevere's abduction in two of his poems, and the medievalist Roger Sherman Loomis suggests that this tale shows that "she had inherited the role of a Celtic Persephone".Chrétien de Troyes tells yet another version of Guinevere's abduction, this time by Meleagant (whose name is possibly derived from Melwas) in Lancelot, the Knight of the Cart.The name is given as Guennuuar in Caradoc's Vita Gildae, while Gerald of Wales refers to her as , no.
A version of the abduction of Guinevere is associated in local folklore with Meigle in Scotland, known for its carved Pictish stones.
In medieval romances, one of the most prominent story arcs is Queen Guinevere's tragic love affair with her husband's chief knight, Lancelot.
This story first appeared in Chrétien de Troyes's Lancelot, the Knight of the Cart and became a motif in Arthurian literature, starting with the Lancelot-Grail of the early 13th century and carrying through the Post-Vulgate Cycle and Thomas Malory's Le Morte d'Arthur.
Welsh tradition remembers the queen's sister Gwenhyvach and records the enmity between them.
While later literature almost always named Leodegrance as Guinevere's father, her mother was usually unmentioned, although she was sometimes said to be dead; this is the case in the Middle English romance The Awntyrs off Arthure (The Adventures of Arthur), in which the ghost of Guinevere's mother appears to her daughter and Gawain in Inglewood Forest.