Rod Stewart has vowed his eighth child will be his last.

The 'Maggie May' rocker - who announced earlier this month he and 39-year-old wife Penny Lancaster are expecting their second baby together - is delighted to be extending his family further but admits he worries about the cost of supporting all his kids.

Rod - who has six children from four previous relationships, as well as four-year-old Alistair with Penny - said: "I'm very happy but it will be the last. I can't have any more kids, otherwise I'll be touring until I'm 90."

Rod - who found out about the pregnancy when he and Penny were celebrating their third wedding anniversary in Italy three months ago - has broken the news to his other children and says they are thrilled that he and the blonde beauty are finally adding to their family.

He told Australia's 'Channel 9 News' programme: "They've known for a couple of years we've been trying for a baby and they're delighted."

Although they don't know the sex of the baby, the 'Sailing' hitmaker said if it is a boy he will follow his tradition of giving him "a Celtic name".

The 65-year-old star also promised fans will get a glimpse of the youngster when he is performing live.

He said: "I might bring them out on stage once or twice, I wouldn't want to exploit him or her though.

"It's good for the kids to see where their daddy works."

Rod's other children are Kimberley, 30, and Sean, 29, with his by first wife Alana Hamilton. He also has Ruby, 23, by model Kelly Emberg and Renee, 18, and Liam, 15, by his second wife Rachel Hunter.

His eldest daughter, Sarah, 46, was born when he was 19 and was brought up in a children's home until she was four, before being adopted.