It’s all about family forRod Stewart.

“#happybirthday@thekimberlystewart! Can’t believe you are 40! You looked radiant last night!#birthdaybash. A mother’s reunion!” Emberg captioned her post.

Kelly Emberg/ Instagram

Rod Stewart and the mothers of his kids

From L to R: Alana Stewart, Penny Lancaster, Rod Stewart, Kelly Emberg and Rachel Hunter.Kelly Emberg/ Instagram

Rod Stewart and the mothers of his kids

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But Kimberly wasn’t the only Stewart celebrating a birthday this week.

Although he doesn’t officially turn 39 until Sept. 1, Sean and mom Alana met up with Lancaster and Rod for “a wonderful early bday lunch,” he captioned an image of the foursome.

“Celebrating Seans birthday in true Stewart fashion 😜 ,” Lancaster wrote alongsidethe same Instagram photo, which notably featured Rod pulling a hilarious face for the camera.

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The birthday outings come almost a year after Rod enjoyed a beach day with Lancasterand all four of his sons, whenhis wife of over a decade shared a photo of the six on Instagram.

“Family time down in Malibu,” Lancastercaptioned the snapshot.

Rod is slated to resume performances of hisLas Vegas residency, Rod Stewart: The Hits,at The Colosseum at Caesars Palace on Sept. 18.

He will then head to California for two concerts, before returning to Vegas and then crossing the pond to play shows throughout the U.K. in November and December.

source: people.com