The left-back came off the Blues Academy production line to earn professional terms in the summer of 2016, when he penned a two-year deal.
Born in Berkshire, Seddon joined Blues from Reading after a successful trial.
He clocked up eight games for the Development Squad whilst still a scholar, and has subsequently racked up more than 50 appearances for the Club's Under-23s side.
Seddon was included in the First Team matchday squad for the first time in early 2018 for the FA Cup game against Huddersfield Town but has yet to make his debut.
The youngster penned a new one-year deal in May 2018, which runs until 30 June 2019, plus a one-year otion clause in the Club's favour.
On 30 August 2018, Seddon joined League Two side Stevenage on loan, initially until January 2019.