The father-of-one has not officially confirmed the newborn's arrival with a statement, but has released a picture of him and his son asleep on a bed. The news comes as a shock, as the pregnancy was never announced publicly.
In the picture, which has since been removed from his social media account, the 35 year old is wearing a football shirt with the number 3, which is Ashley's number for his current team LA Galaxy, and the word 'king' whilse his son's matching top says 'prince'.
A friend of the couple told The Sun; 'It's a beautiful picture and shows Ashley in a different light. Everyone has a past but this is now his future. Everyone hopes he will be the fantastic father we all know he can be.'
The ex-husband of Cheryl Fernandez-Versini found out he was going to become a father with his Italian girlfriend Sharon Canu in December.
Sharon's grandfather, Mr Buzzelli, told The Mirror newspaper: 'Ashley is very happy. He's a good guy - and my granddaughter is a beauty.'
The father-of-one had to miss the USA Champions League quarter-final on Sunday because of the birth, which took place in Rome, but has now returned to Los Angeles to be reunited with his squad.
Their relationship has been kept largely out of the limelight, Sharon reportedly comes from a normal Italian family and they have only been pictured together once at a London club last June.
Ashley was previously married to X Factor judge Cheryl for three and a half years after a lavish wedding ceremony, which cost over £1,000,000 in July 2006.
The pair split after Ashley's cheating was exposed with hairdresser Aimee Walton.
The Fight For This Love singer has told InStyle magazine that she was left 'coping in public but crumbling in private' over the break-up.
The Newcastle-born star was most recently married to French businessman Jean-Bernard Fernandez-Versini but is reportedly seeking a divorce.