Brady, a winger, has impressed former United fullback Arthur Albiston this season.
Albiston told the Manchester Evening News: "Has been the captain and has a great attitude. He is a really chirpy character.
"The 17-year-old Dubliner really gets stuck in and can play central or wide left midfield - but he also takes the knocks as well as giving them.
"Robbie has a good physique. He's not tall but jumps well and can drop a ball on a sixpence."