Brian Austin Green Shares Rare Photo of Sharna Burgess and His 4 Sons for Mother’s Day: ‘Rock of This Family'

Brian Austin Green is celebrating Mother's Day with his family.

On Sunday, the Beverly Hills, 90210 actor, 50, took to social media to share a glimpse into his life with his fiancée Sharna Burgess their son, Zane, 23 months and his three other young sons: Noah Shannon, 11, Bodhi Ransom, 10, and Journey River, 7, whom he shares with ex-wife Megan Fox.

"You stepped into this world (which could not have been farther from the one you knew) and have become the rock of this family," Green captioned a photo of the Dancing with the Stars pro dancer, 38, lounging in bed with Zane and her three young stepsons.

"You are an incredible mother and fiancé [sic] and we all love you to death 😊 Happy Mother’s Day baby ❤️❤️."

The actor's eldest son Kassius Lijah, 21, with ex-girlfriend Vanessa Marcil, didn't appear in the photo.

"Oh my gosh 😭♥️ The best thing that ever happened to me was you and those babies right there," Burgess wrote in the post's comments section.

"You were all always a part of my future and my story and I wouldn’t have it any other way," she continued. "I am the luckiest, and I love you all so much ♥️ Thank you for making me a mama."

In a January episode of his podcast Oldish, Green said Zane's birth made him look at fatherhood differently.

"So, funny story. I haven't really planned for any of my kids," he explained after being asked if he would consider having more children.

"Every time, it's been, 'Oh, it's OK. We can do this.' I love my kids, and I wasn't against any of them, but I've never experienced that thing of looking at a pregnancy test and hoping that it's positive and preparing that way," he continued.

During the podcast, Green added that Zane's birth inspired him and Burgess to look at the logistics of having more kids. In the end, the actor shared how he decided to get a vasectomy when Zane was 8 weeks old.

"Zane was born, and I was like, 'I think it's time to close the shop,'" Green said.

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"If we do it again, I do want the experience of us planning it together, doing the pregnancy test, and really being on this journey with each other," Burgess added. "So, we would probably end up having to do IVF [in vitro fertilization.]"