son of Bertram Prat. He held Knarsdale in Northumberland, and likely was from the 'of Tynedale' Prats. Was a minor in 1296 and in the custody of John Wishart of the Carse (having been in his custody since at least 1288). Not to be confused with an earlier John Prat, son of Bertram, who appears from the 1250s.