Which knight is the son of Sir Lancelot and Elaine of Corbenic, from Arthurian legend?

Sir Galahad (sometime referred to as Galeas or Galath), in Arthurian legend, is a knight of King Arthur's Round Table and one of the three achievers of the Holy Grail. He is the illegitimate son of Sir Lancelot and Elaine of Corbenic, and is renowned for his gallantry and purity.

According to the thirteenth century Old French Prose Lancelot "Galahad" was Lancelot's original name, but it was changed when he was a child. At his birth, therefore, Galahad is given his father's own original name. Merlin prophesies that Galahad will surpass his father in valor and be successful in his search for the Holy Grail.