Rod Stewart Celebrates Pregnant Daughter Ruby at Baby Shower with Family: Photo

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

Rod Stewart is gearing up to become a grandfather for the second time.

The 78-year-old rocker was all smiles at a recent baby shower celebrating daughter Ruby Stewart 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 Monday.

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

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RELATED: Rod Stewart Poses with Wife Penny and Six of His Children in Rare Holiday Family Photo

Last month, 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."

Rod Stewart/Instagram

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

The reveal of his second grandchild's sex appears to have taken place over the holidays, as all wore the same clothing as they did in a rare family photo Rod shared to his Instagram Story on Dec. 28 when he posed with wife Penny and six of his eight kids in front of a giant, lit-up Christmas tree.

Adding a "family time" sticker to the post, Rod stood happily with sons Aidan, 11, and Alastair, 17, whom he shares with Lancaster, as well as adult children Renee, 30, Ruby, 35, Sean, 42, and Kimberly, 43.

The group was also joined by Kalick and Delilah.

Not pictured in the photo were Rod's daughter Sarah, 58, whom he and ex-girlfriend Susannah Boffey placed for adoption as teens, and son Liam with ex-wife Hunter, whom he was married to from 1990 to 2006.