Sean Stewart Turned to Dad Rod's Jeweler to Design Surprise Engagement Ring for Wife: All the Details

Sean Stewart has done well with his diamond ring choice for his new wife, Jody Weintraub.

The oldest son of rocker Rod Stewart, 42, purchased the ring from Ron Rosenblum at XIV Karats in Beverly Hills, Rod's longtime jeweler who spoke exclusively with PEOPLE on the 3-carat sparkler Sean picked up on Tuesday.

"It's nice. It's exciting. I was one of the first ones, I guess, that he called and said, 'guess what? I got great news. I got married!'" Ron tells PEOPLE.

The couple, who have known each other for nearly 30 years, married in Las Vegas on Valentine's Day in a spur-of-the-moment wedding after he proposed at dinner that night, PEOPLE exclusively confirmed from a source last week.

"Sean asked her while they were out to dinner at Catch. They married shortly after getting their marriage license at 10 p.m. at Little Church of the West," a source close to the couple exclusively told PEOPLE. After heading back to Los Angeles and celebrating with family at Nobu Malibu, Sean set out for his most important task: choosing the ring.

RELATED: Rod Stewart's Son Sean Stewart Marries Jody Weintraub in Las Vegas: Source

Alana K Stewart Instagram Sean Stewart and Jody Weintraub

"We looked at three beautiful different options," Ron says of walking Sean through the process for something special for Jody, also 42. "What she wanted before he even kind of knew what he was looking for was what he wound up with because that's what her desire was."

"It's a really super super fine quality 3-carat cushion [cut]," Ron says of the six-figure ring. "Full pavé. Everything pavé pavé," he says of the famed French setting.

"So he was very sweet and gave her what she wants," says Ron of Jody's "dream" ring, which she had shared a picture of something similar. "All girls have this inspiration. That's what her dream was and that's what he fulfilled," he shares, adding of Sean: "He's a good guy. He's really a good guy. He's fun."

Ron, who has designed some memorable Celtic pieces for Rod over the years, has known the family for decades, explaining that Sean certainly has an eye for luxury like his dad.

"He grew up in it," he says matter-of-factly. The British musician, 78, dubbed "Rod the Mod" in the mid-sixties, is known for paving the way with his signature style starting from his much earlier years with The Faces in 1969 before building his mega-successful career.

Despite Sean's famous upbringing, he's poured his heart and soul into his own recent business endeavors, the Stewart source says, with his apparel company Dirty Laundry — striving to build his own empire, now with his own new family. Jody has a son, Doc, age 5, who Sean adores.

Bauer-Griffin/GC Images Rod and Sean Stewart

Shortly after PEOPLE's wedding story broke, Sean's mom Alana Stewart, who was married to Rod from 1979 to 1984, confirmed the wedding news with a sweet congratulations to her son and his "beautiful bride" on Instagram.

RELATED: Rod Stewart's Ex-Wife Alana Says She's 'So Happy' for Son Sean After His Impromptu Vegas Wedding

The streetwear designer has known the former EXTRA producer, daughter of the legendary late producer Jerry Weintraub, since high school, the source explains. "They are both very family-oriented people."

Jerod Harris/Getty Images

Ron the jeweler concurs. "They come from two great families, so good for them," he tells PEOPLE, explaining that Sean came in on his own to purchase the ring and presented it to Jody on Tuesday.

RELATED:  Rod Stewart Says Getting Married at 34 Was Too Young: 'I Had a Lot of Partying, Drinking and Shagging to Do'

jodi stewart/instagram Sean Stewart, Jody Weintraub and Rod Stewart in 2022

As for the last-minute nuptials, the couple intended on just taking a typical romantic trip for Valentine's Day to the Wynn hotel, but then it quickly turned into a lifetime commitment. "Sean and Jody share a best friend, Courtenay Semal, which was the reason why they kept reconnecting over the years. They both have famous families, they just get each other," the source says, noting that the couple is "so much alike" and are "born two days apart" from one another.

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With his new wife, Sean is "proud" to finally have a family of his own, and the source shares that he and Jody plan to have children together. For now, it's house hunting and planning a traditional wedding this summer in Spain at Marbella Beach Club with their families.

"They're the same person," the source adds of the couple and why it works. "They're from the same town, they have the same friends. They just understand each other."