Rod Stewart Shares Throwback Photo with Sons Alastair and Aiden Cheering on Celtic Football Team

Sir Rod Stewart/Instagram Rod Stewart and sons Alastair and Aidan

Rod Stewart is recalling some fun memories with two of his boys.

Sharing a throwback photo first posted by son Alastair Wallace, 17, the 78-year-old rocker stood with the teenager and younger son Aiden Patrick, 12, at a Celtic Football Club soccer match. All three of the Stewart men were decked out in club gear.

The photo was also shared by wife Penny in a since-deleted Instagram Story. In addition to the couple's two sons, Stewart is also dad to adult children Renee, 30, Ruby, 35, Sean, 42, and Kimberly, 43.

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Rod Stewart Instagram

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Stewart first became a grandfather in 2011, when his daughter Kimberly Stewart and actor Benicio Del Toro had their daughter, Delilah, now 11.

He is looking forward to becoming a grandfather for the second time, recently attending a baby shower celebrating daughter Ruby and her partner Jake Kalick as they prepare to welcome their first baby.

Rod posed with Ruby and Jake, ex Kelly Emberg, and Kalick's parents in a sweet photo that Emberg shared on Instagram last month.

Kelly Emberg/instagram Rod Stewart poses with ex Kelly Emberg, daughter Ruby Stewart and her partner Jake Kalick, and his parents

She captioned the shot with hashtags, "it's a family affair," "we are having a baby" and "boy."

In January, Ruby shared a video of the joyous moment she learned she was having a boy — news that was broken by her dad, who read the baby's sex off of a sealed piece of paper.

In the clip, cheers erupted when Rod made the proclamation "It's a boy." Ruby cupped her mouth and laughed, then hugged Kalick. Rod fist-pumped, and shouted "Born a Celtic!" in honor of his favorite soccer team, Glasgow Celtic.

He then began singing, "another winkle in the Stewart family."

Ruby captioned the post, "Hire @sirrodstewart for your gender reveal! He will even write a custom jingle for your unborn child."