Robbie is said to be over the moon about the news, as he really wanted his two-year-old daughter Theodora Rose (known affectionately as Teddy) to have a brother.
When he announced that Ayda was pregnant in April, Robbie said,
"We don't know if it's a boy or a girl but we're going to find out. If we have a girl, it'll be totally cool but I would quite like a little boy.
"With Teddy, the doctor put the sex into an envelope. We went to dinner and the plan was to open it at the end of dinner... but she forgot the envelope. "I think we're going to do the same thing - but remember the envelope this time. I don't think we can do it any other way."
Robbie and Ayda went ahead with their plan to and thankfully this time they did remember the envelope!
"Robbie is expecting a boy and is over the moon," a 'source' close to Robbie told The Daily Star.
"They went for scans recently when they were in LA and once again got the doctor to put the sex of their baby in an envelope so they could take it away and open it later.
"They went out for dinner and opened it after dessert.
"Both Robbie and Ayda are thrilled. Robbie wasn't shy about telling the world he wanted a son and now they are expecting one."
Ayda is due to give birth in October and it's thought she will have her little boy in the same private hospital in London where Theodora was born in September 2012.
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