Thomas Ravenel and ex-girlfriend Heather Mascoe welcomed their baby boy on June 29

Jonathan Jackson Ravenel Thomas Ravenel
Thomas Ravenel's son Jonathan
| Credit: Thomas Ravenel/Twitter; Inset: Charles Sykes/Bravo/NBCU Photo Bank/NBCUniversal via Getty

Thomas Ravenel's baby boy has made his social media debut.

Jonathan Jackson — whom the former Southern Charm star welcomed with ex-girlfriend Heather Mascoe on June 29 — is too cute in the first photo Ravenel, 57, posted of the newborn on his Twitter account Thursday morning.

Wearing an unbuttoned animal-print pajama set and a diaper, baby Jonathan peers up at the camera from atop what appears to be a striped pillow or blanket.

"Meet Jonathan Jackson Ravenel. One 5 weeks old," the proud father tweeted to accompany the snapshot.

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Thomas Ravenel
| Credit: Rebecca Miller/Bravo/NBCU Photo Bank via Getty

The former South Carolina state treasurer first revealed his baby news to the Daily Mail last month.

"We've named him Jonathan Jackson Ravenel and he was born by c-section on June 29, 7 lbs., 4 oz. and 20¼ inches long," Ravenel told the publication. "We are both very happy. Heather is a phenomenal mom and they're both doing well."

Baby Jonathan is Ravenel's third child and first with Mascoe, 38, whom he told DM he is "really good friends" with. He is also dad to two kids with ex Kathryn Dennis: son Saint Julien, 4½, and daughter Kensie, 6.

"It's kind of difficult to explain to them, you know, 'This is your half-brother – different mothers, same father.' They were a little confused," he added in his interview with the U.K. outlet. "In the end I just told them, ''You'll understand when you're older!' "

Ravenel and Mascoe were first linked last April, though had split by August, a source told PEOPLE. She has two children from a previous relationship.

Kathryn Calhoun Dennis
Kathryn Dennis and Thomas Ravenel with their two kids
| Credit: Kathryn Calhoun Dennis/Instagram

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Dennis, 29, and Ravenel's romance played out throughout their time together on Southern Charm, the two dating in the first season when she was a 21-year-old college student. They split shortly after Dennis gave birth to Kensie but reunited in 2015, just long enough to conceive their son.

After a lengthy battle, Ravenel and Dennis agreed to share joint legal and physical custody of their two children. Ravenel was given "primary legal custody," his lawyer told PEOPLE at the time.

Since then, the former couple have been co-parenting their kids and have spent time together socially. In January, they attended a James Bond-themed party and posted a photo posing alongside each other.

Their friendly night out sparked rumors that the two were dating again, but a source told PEOPLE at the time they were in no rush to jump back into anything. (Both Ravenel and Dennis have also publicly denied on their respective social media accounts that they're dating.)