Ser Walder Rivers is a natural son of Lord Walder Frey, and is often called Bastard Walder. He is the eldest of Lord Walder’s bastard children. He is a gruff, dour and has grey hair. Though not a trueborn Frey, he is often put in positions of responsibility for the house due to his strong reputation as a warrior. His mother fell from a horse and died. His personal coat of arms is a silver-grey castle on blue (the colors of House Frey reversed) beneath a red bend sinister.