A spokesman for the pair said: “Mother and baby are healthy and blissfully happy,” Aiden was born on Wednesday weighing 7lb 12oz.
The singer has never hidden his love for Celtic and was at last month’s 4-0 home win against Hearts.
Aiden already has a big brother Alastair with dad Rod now a father of eight with Aiden having half brothers Liam and Sean.
After finding out that he was going to be a dad again Stewart said: “I can’t have any more kids, otherwise I’ll be touring until I’m 90.”
It’s not known if the new dad will be in his Directors Box seat for Sunday’s match against Rangers.
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