Ariana Grande's Cozy 25th Birthday Party Included Both Her Mom and Fiance Pete Davidson (Exclusive)

Ariana Grande Grammys 2015
Jason Merritt/Getty Images

Ariana Grande's 25th birthday celebration was a family affair.

Ariana Grande's 25th birthday celebration was a family affair.

An eyewitness tells ET that the singer celebrated her milestone birthday at Frames Bowling Lounge NYC on Tuesday night with her mother, Joan Grande, and fiance Pete Davidson in attendance.

According to the eyewitness, Grande and a group of about 28 people arrived around 8 p.m. and took over a private blacked-out karaoke room. The eyewitness adds that security was heavy, with not only the venue’s security team escorting the group in through a private entrance, but Grande's security team as well.

On Tuesday, Grande shared a few snippets of her singing karaoke on her Instagram Stories. Not surprisingly, she completely slayed Beyonce's "Love on Top," while Davidson showed off his rapping skills to Eminem's "Superman."

Grande and Davidson also sang Evanescence's "Bring Me to Life" together.

Grande's celebration included two cakes that were delivered -- one 40-pound cake with exploding sprinkles inside and another cake in the shape of a cloud with the birthday girl's name on it -- the eyewitness later notes. After karaoke, party guests originally planned to go bowling until 1 a.m., the eyewitness says, but the bowling area wasn’t as secure as they would have liked, so the group left at 11 p.m. 

Earlier this month, a source told ET that Grande has also met Davidson's mother and the two appeared very much at ease with one another.

“Pete introduced Ariana to his mother at Zuma in New York during one of the SNL after-parties,” the source said. “Ariana spent the majority of the night hanging out with her [Amy Waters Davidson]. Pete was circulating the room with the cast but Ariana was super comfortable being with [Amy].”

On Tuesday, Davidson took to social media to publicly wish his fiancee a happy birthday.

"Happy birthday to the most precious angel on earth!" Davidson Instagrammed alongside a snap of him giving Grande a piggyback ride. "You’re my favorite person that ever existed :) I love you sm."

"One more for the queen," he captioned a photo of the two hugging. "Words can’t express what a real f**king treasure this one is."

Watch the video below to see the couple's cutest moments:

-- Reporting by Joseph Corral

RELATED CONTENT: