Ruby Stewart and Fiancé Jake Kalic Welcome Baby Boy: 'Unlike Any Other Love'

Ruby Stewart is officially a mom!

The singer and model, 35, and fiancé Jake Kalic welcomed a baby boy named Otis Stewart Kalick, she revealed on Instagram over the weekend.

The Mother's Day announcement came five days after the little one was born on May 9, as Stewart shared a heartfelt caption to mark the occasion.

"This love… unlike any other love I've ever known," Stewart wrote of the baby photos. "I am only a mirror of what I feel from you… I can't remember what life was like before you…. But nothing else matters now that you're here… Your arrival into the world marks the beginning of our family… it all started with you Otis."

In Otis' first photos, he can be seen smiling while holding his face, showing off his big eyes and even bonding with his mom in a third pic. He was born at 3:36 p.m., weighed inat 8 lbs., 8 oz. and is 22 inches long, Stewart shared.

Ruby's sister Renee commented on the photos: "Love you so much… can't wait to meet you Otis! ❤️ Aunty Nay Nay x"

Jake also shared an image of Otis to Instagram, writing: "Otis Stewart Kalick showed up, 12 days late for his reservation, happy and healthy. Otis' Mom is incredible. Happy first Mother's Day @rubystewart."

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Ruby's father, Rod Stewart, was all smiles at a February baby shower celebrating the couple as they prepared to welcome their little one, the first baby for each.

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."

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.