Waldo Brown is the son of Arthur Brown and Nel Poot, and the brother of Dilly-O and Sorrel. He and Dilly-o are twins. He was named after Oswald Chitter. He is very artistic, and when Gervase Brightkin visited Holeborn he gave Waldo some brushes and encouragement.
- Waldo, his sister and brother will apparently play a key role in the final battle against the Raith Sidhe. According to Robin Jarvis: "It is with [Arthur Brown's] children that the hope of the world will reside."