The little boy was born on February 16 and weighed in at 7lb 12oz. The couple, who already have a five-year-old son Alastair, revealed last year that they were expecting a little boy.
A rep for the pair told hellomagazine.com: 'After the long awaited arrival of their second child, Rod and Penny are proud and thrilled to welcome Alastair's baby brother Aiden into the world.
'Born February 16th 2011, weighing 7lb 12oz, mother and baby are healthy and blissfully happy.'
The couple announced in August 2010 that they were expecting again after revealing they went through three rounds of IVF before Lancaster, 39, fell pregnant.