Jon


In Thomas Chestre’s Sir Launfal, a nephew of Arthur and brother of Howe.

Jon and Howe accompanied Sir Launfal when Launfal fled to Caerleon to escape Guinevere’s disfavor. When Launfal fell into poverty and depravity in Caerleon, Jon and Howe returned to Arthur’s court.


Source
Sir Launfal | Thomas Chestre, late 14th century