Sir Lavaine was the younger son of Sir Bernard of Astolat (supposedly Guildford) and the brother of Sir Tirre and Elaine the Lily Maid. Lavaine and his brother had recently been knighted when Sir Lancelot, travelling secretly to a tournament at Winchester, stopped at Astolat and lodged with Sir Bernard. Tirre had been wounded the same day that he was knighted and was still lying in bed recovering from his wounds, so his shield was available for Lancelot to borrow as part of his disguise. His own shield, Lancelot left with Elaine for safekeeping - doing for her what he had never done for any other woman, including Queen Guinevere: With a view to heightening his incognito, he accepted Elaine's token to wear in the lists. The lady, of course, fell deeply in love with him. Sir Lavaine went with Lancelot to the tournament, made a good showing and helped his gravely wounded companion away to the hermit, Baudwin. Sent back to Winchester by Lancelot to seek out the latter’s cousin, Sir Bors, Lavaine first encountered his sister Elaine who insisted on going herself to nurse Lancelot back to health. Locating Bors, Lavaine brought them both to the wounded knight. As he would not marry her, Elaine asked to be Lancelot’s paramour and even Sir Bors counselled him to love Elaine if he could, but Lancelot remained true to Guinevere. After Lancelot left her, Elaine died of a broken heart. In accordance with her dying instructions, her body was put in a barge and floated down to Westminster, where the King, Queen, Lancelot and the rest of the Royal Court grieved to see the body and read the explanatory letter in its hand, which requested Lancelot to give the Mass-penny for her soul. Sir Lavaine remained at court after Elaine's death, "and ever in all places Sir Lavaine gat great worship so that he was renowned among many Knights of the Table Round". At Arthur's famous Christmas tournament, Lavaine encountered the King himself in the lists and they knocked each other to the ground. Lavaine was made a companion of the Round Table at the same time as Sir Urre of Hungary whose sister, Felelolie, he later married. Remaining in Sir Lancelot's faction during the break with King Arthur, Lavaine accompanied Lancelot into exile and was eventually made Count of Armagnac.