In Arthurian legen, Sir Kay (Welsh: Cai, Kai, or Kei, or Cei; Latin: Caius or Gaius; French: Keu; French Romance: Queux; Old French: Kès or Kex) is Sir Ector's son and King Arthur's foster brother and later seneschal, as well as one of the first Knights of the Round Table. In later literature he is known for his acid tongue and boorish behavior, but in earlier accounts he was one of Arthur's premier warriors. Along with Bedivere, with whom he is frequently associated, Kay is one of the earliest characters associated with Arthur.