Alastair Stewart and Sir Rod Stewart.Photo:Dave Benett/Getty

Dave Benett/Getty
Rod Stewart’s son is all grown up!
On Tuesday, the rock legend, 78, and wife Penny Lancaster, 52, spent the day with son Alastair celebrating his 18th birthday.
A photo from the day shows the couple lounging on the couch with their son. Later, they all get done up as they step out to continue the festivities out on the town.
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Penny Lancaster and Rod Stewart with son Alastair on his 18th birthday.Penny Lancaster/Instagram

Penny Lancaster/Instagram
Stewart appeared on the cover of the November issue ofHaute Living, where he praised his kids and their accomplishments.
“I don’t think I’m as strict with my kids as my mom and dad —especiallymy dad — were,” Stewart told the outlet. “I’m very lenient with them. None have gotten into any serious trouble. A couple dabbled with drugs, but that’s all done now. I’m very proud of them all.”
He also added that when he’s on the road he misses his family “so much,” and that his loved ones are “a wonderful luxury” when he returns home.
Stewart family.Kimberly Stewart/ Instagram

Kimberly Stewart/ Instagram
According toHaute Living, Stewart already has eight grandchildren.
source: people.com