Brian Austin Green Talks Baby Zane, Expanding His Family, and His New Mockumentary (Exclusive)

The actor and new dad spoke with ET at Comic-Con 2022 on Thursday.

Brian Austin Green is excited about his 3-week-old son, Zane, but thinks that five kids might be enough for him at the moment.

The new dad spoke with ET's Matt Cohen at San Diego Comic-Con on Thursday, where he was promoting a new mockumentary project, Bootyology, and he opened up about welcoming his fifth son with girlfriend Sharna Burgess, in June.

"He's amazing! I mean he's only 3 weeks old at this point," Green shared. "But Sharna's amazing, she an amazing mom."

Apart from his newborn son Zane, Green is also the father of three sons with ex-wife Megan Fox -- Noah, 9, Bodhi, 8, and Journey, 5 -- and has a 20-year-old son, Kassius, from his relationship with Vanessa Marcil.

"I mean, I have five kids, and we joke about the fact that I had a I already had a station wagon [before Zane], so now I have [to get] a Yukon Denali," Green joked. "If I have another one, then I'm moving to like a school bus or something."

"How do you travel? Like, you know, going into a restaurant asking for a table for seven, it all starts becoming a little much," he added. "So I think I'm done at five."

While he seemed confident in that being the right number of kids, Green didn't set it in stone, adding, "I'm not saying never, you notice, I'm saying, 'I think.' And there's a lot that can come from thinking. There's a lot of room for change within that."

As for his adorable baby boy's relationship with Green and Fox's young sons, the actor said that they've all been very harmonious, even before the baby was born.

"The kids are so amazing with Zane, they were amazing with Sharna the whole time when she was pregnant," he recalled. "They would come in every morning and they would wanna rub her belly and they would talk to him and they're just obsessed with him. They come in every morning now, going, 'Is he awake yet?' You know, they tip toe around, they're so cute, its so cool."

"It's just been really smooth sailing," he added with a smile. "It's been great."

Meanwhile, a source tells ET that Sharna "absolutely loves being a mom and wouldn't ask for anything better or more in the world."

"She is on cloud nine and Brian is right there beside her, waiting on her hand and foot. They truly couldn't be happier," the source says. They feel like this is the greatest gift of all time and it's almost unexplainable how happy they are. They are absorbing every beautiful moment of this process and soaking up this experience for all that it's worth right now."

The source adds, "Brian's other children are adjusting, but very happy to have a new baby brother. Getting engaged and married is definitely in the pipeline."

While his baby boy is at the forefront of his mind, Green is also working hard to promote his new film, Bootyology, a mockumentary following a rap duo The Booty Boys, who went missing for years after getting accidentally frozen. When they are unthawed in a different era, the two have a hard time adjusting to the way the world and culture has changed as they attempt a comeback.

"Its a documentary following The Booty Boys, who were a rap group in in the early 2000s," Green told ET of the new comedy project, in which he plays himself. "It's awesome, and if you're a fan of hip hop, they're super entertaining and super fun."

According to Green, he first got involved in the project through his girlfriend, while they were competing on Dancing with the Stars.

"She originally came to me she was like, 'Hey, so the guys that do music on the show, they're doing this film and want to talk to you about it,'" Green recalled. "When I heard about it and I got the description of it, was like, 'That's awesome, I have to it!'"

Bootyology is positioning for a streaming release in early 2023.

See below for more of Entertainment Tonight’s ongoing coverage of Comic-Con 2022, including the daily schedule and biggest highlights of the weekend