Kia who trained with the Manchester United development team in October has been a regular of recent at City Football Academy.
Rooney, a Manchester United legend, second in the all-time top scorers for the club with 248 goals in 248 appearances.
In fact, the 31-year-old is just a goal behind United all-time top scorer, Bobby Charlton who has 248 goals.
So it will come as a shock and disappointed to some fans that his son has started training with the Academy of their bitter rivals, Manchester City.
Kai who trained with the Manchester United development team in October has been a regular of recent at City Football Academy.
According to Daily Mail, the 7-year-old has impressed his coaches at City since he started training with them.
Rooney is said to have been at the City Academy training ground to watch his son play along with his own father, Wayne snr.
The reports, however, note that it is normal for youngsters to play for a number of academies before choosing a team.
Rooney has two other sons, Klay, three, and 10-month-old Kit.
The England captain is not the only Manchester United player whose children have trained at City.
Sons of Robin van Persie, Darren Fletcher and Phil Neville once training at Manchester City Football Academy.