The 65-year-old singer released a statement announcing that he is to add to his brood once again. Stewart already has a four-year-old son Alastair with Penny as well as five children - Kimberly, Sean, Ruby, Renee and Liam - from his previous relationships. His eldest daughter Sarah Sareeter, now 46, was given up for adoption by her mother after a teen fling and has no relationship with her father.
A statement read: "Penny and Rod were lucky enough to be celebrating more than just their third wedding anniversary in June, as the news came that Penny was pregnant with their second child.
"We were thrilled and delighted to be able to tell Alastair that he was going to be the big brother to a little baby, expected just before mummy's 40th birthday."