Famous for playing Harry Batt on the CBBC and BBC children's programs Dick and Dom in da Bungalow and The Legend of Dick and Dom, Kirby is also known for his series regular role as Loaf on the 1980s ITV show Your Mother Wouldn't Like It.
After training at the Central Junior Television Workshop, he studied at the famous Royal Academy of Dramatic Art (RADA) and went on to perform with the Royal Shakespeare Company.
He appeared in every single episode of the children's talent program The Slammer.
He was born and raised in Nottingham, England.
He appeared with Rafe Spall in the short-lived Channel 4 comedy series Pete versus Life.