Baldwin spoke to PEOPLE about his daughter’s new baby at the People + Chain 50th anniversary party in Los Angeles on Sept. 13

Stephen Baldwin is one proud grandpa!

Speaking exclusively to PEOPLE at the People + Chain 50th anniversary party at The Chain House in Los Angeles on Friday, Sept. 13, the actor and father of Hailey Bieber shared some details about his “incredibly cute” new grandson, Jack Blues Bieber, whom Hailey, 27, welcomed with husband Justin Bieber in August.

Stephen, 58, has been on grandpa duties lately, telling PEOPLE he’s been “hanging out with my four year old granddaughter Iris. I’m in town to celebrate her fourth birthday and the launch of the podcast and all that,” he explains, referring to his daughter Alaia’s little girl, Iris Elle Aronow.

“And of course, here comes Jack Blues Bieber. And yeah, he’s just… I don’t want to say too much. He’s unbelievably cute,” the actor adds of his new grandson.

Stephen also hints that Jack Blues might be making a public appearance in the near future, saying that, “the world will see him soon.”

Related: Justin Bieber and Wife Hailey Announce Arrival of First Baby: ‘Welcome Jack Blues Bieber’

Justin, 30, first announced the arrival of the couple’s son in an Instagram post on Aug. 23, sharing a photo of Jack Blues’ foot with the caption, “WELCOME HOME JACK BLUES BIEBER 🐻.”

At the time, Stephen reacted to the news with a cute post on X (formerly Twitter) on Aug. 25, sharing the photo of the baby’s foot and writing, “#Congratulations Mr&Mrs Bieber 🎈 #Grandson ❤️‍🔥 #blessed.”

Related: Justin Bieber Shows Off Adorable ‘Papa Bear’ Mug in First Post Since Welcoming Son Jack Blues with Wife Hailey

Meanwhile, shortly after the news of Jack Blues’ arrival, a source revealed exclusively to PEOPLE on Aug, 26 that the singer is “already a great dad” and that their son was something the couple had “wished and prayed for.”

“The pregnancy was something that they very much wished and prayed for. The day they found out that Hailey was pregnant, was the best ever for Justin,” the source said.

“He was over the moon with excitement. It was a big celebration for them,” the insider added.

The new parents are “both overjoyed” after the arrival of their son, the source said, adding that, “The baby is such a miracle. He’s adorable and doing well. Hailey’s doing well too.”

Since then, Hailey has posted a photo showing off a new ISA Grutman diamond and gold “MOM” ring on her Instagram Stories on Sept. 3, while Justin posted a carousel of images the same day that featured a snap of a coffee mug with a cartoon bear holding up a heart and “Papa Bear” written on it.