Ant Anstead Pays Tribute to Renée Zellweger on Her 53rd Birthday: 'You Are Pure Class'

Ant Anstead is showing his partner some love on her birthday!

On Monday, the Wheeler Dealers alum shared a tribute to girlfriend Renée Zellweger on his Instagram Story in honor of her 53rd trip around the sun, penning a short but sweet message to the Bridget Jones actress.

"Happy Birthday to this beautiful Lady!" Anstead, 43, wrote alongside a black and white photo of the pair cuddling up to each other, adding, "Ren you are PURE CLASS! I know how lucky I am."

Anstead and Zellweger started dating shortly after meeting on the set of his Discovery+ show in June last year. The pair made their first public appearance as a couple in August and went Instagram official with their relationship a month later.

"There is so much respect between them," a source told PEOPLE in September. "They spend as much time as possible together when they aren't working on other projects. They truly like each other as well as their romantic attraction. The relationship is serious."

"Renée has found love again, a love where she feels confident and secure about herself," added the source. "And Ant, too, has had a lot of ups and downs, but seems to have stability in this romance."

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The couple has also experienced many "firsts" in the past months. While visiting California from the U.K. for Christmas, Anstead's two older kids — daughter Amelie, 18, and son Archie, 15 — got to meet Zellweger in person for the first time.

"It was great," the car expert said. "I mean, Renée's so personable, and so great with people, and they've met a few times on FaceTime, so everybody was excited to finally get together."

He continued: "Of course, everybody got on famously. It's really nice."

Meanwhile, in an April cover story for Harper's Bazaar, the Oscar winner opened up about the beginnings of her relationship with Anstead for the first time.

At the time she met the British-born television personality, she was still mourning the loss of her friend and publicist Nanci Ryder, who died of ALS in 2020 at 67.

"It was around Judy," Zellweger told the outlet. "Late night, and I remember I watched the Property Brothers with Brad Pitt." The feature's author, Mickey Rapkin, clarified that she wasn't binge-watching alongside Pitt but rather referring to the actor's appearance on HGTV stars Drew and Jonathan Scott's series, Celebrity IOU.

RELATED: Ant Anstead's Girlfriend Renée Zellweger Met His Older Kids at Christmas: 'Got Along Famously'

The show features A-listers paying back friends and mentors who have helped them get where they are today by surprising them with a home makeover facilitated by the handy twins.

The outlet reported that Zellweger felt compelled to give back to the two twin brothers and nurses who cared for Ryder during her illness, Jerome and Jerald Cowan.

At the time, a spin-off show titled Celebrity IOU: Joyride was in development. It featured the same starry concept, but with amazing custom cars instead of home Renos as the gift. Intrigued by the prospect, Zellweger decided to participate.

She met Anstead – the show's host – on set, and the pair quickly hit it off.

When asked by the outlet about whether Ryder, in a way, brought the two together, she responded, "Yeah, we do joke about that. She's always doing her best. It made me smile. It made me smile to think on this, yeah, the serendipity of it all."