“It’s a recent engagement. They’re just two people who found love quickly and make each other happy all the time. They both started talking about it this past weekend. It’s nothing they’ve been hiding,” says a source close to the couple.
Reps for the stars, both 24, did not immediately respond to PEOPLE’s requests for comment.
Grande tweeted an emoji-filled message moments after the news went public on Monday afternoon. “I love you,” she wrote, flanked by tons of laughing monkey faces. She continued by writing “sm” (presumably “so much”) before adding more monkey faces and signing off with “ok bye.”
The pair — who began dating shortly after Grande’s breakup from rapper Mac Miller in May — have been using social media to express their affection for one another. Davidson also confirmed that he had split from his longtime girlfriend Cazzie David in mid-May, around the same time he wrapped his fourth season performing on Saturday Night Live. He will reportedly return to the show when it resumes production in the fall.
Over the weekend, they headed to Mastro’s in Beverly Hills to celebrate Grande’s mother Joan’s birthday. The group tucked into mashed potatoes, caviar, kobe beef, crab legs and more as they celebrated.
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Multiple sources previously told PEOPLE last month their relationship had “just started” and was “very casual.”
Davidson was on hand to support Grande as she performed at the Billboard Music Awards. “After Ariana’s performance, they were backstage and he had his arm around her,” an onlooker told PEOPLE. “They seemed very lovey-dovey. He was hanging out with her and her friends with his arm around her. She seemed quite smitten.”