Sharna Burgess Celebrates Boyfriend Brian Austin Green's Birthday with 'Mushy Instagram Post'

brian austin green, sharna burgess
brian austin green, sharna burgess

Matt Winkelmeyer/Getty Brian Austin Green and Sharna Burgess

Sharna Burgess is celebrating boyfriend Brian Austin Green on his birthday.

Green turned 48 on Thursday, and Burgess marked the occasion with a sweet Instagram photo of the Beverly Hills, 90210 actor lounging in a pool, as well as several throwback pics.

"Mushy Instagram posts aren't really your thing… but they are definitely mine so…" she began in the lengthy caption. "Also … you can thank your mum for the next few slides."

The Australian dancer, 36, continued, "You are my best friend and my favorite human, it's hard to imagine before you because this somehow feels like it just always was. I truly never knew it could be like this. That my happiness could find a whole new level. That life and love and all things in between could feel so inexplicably deep and connected and transparent and …. Right."

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"Loving you is the easiest thing I've ever done and I'll celebrate your existence today and all days, In all the ways, always. I love you, HAPPY FRICKEN BIRTHDAY!!!" she wrote. "Cute as hell from birth and you only keep getting better. You deserve everything you've ever wanted, dreamed of, or needed. I know there is so much exciting stuff ahead for you, and I can't wait to witness it."

Burgess then revealed that the couple is going diving with sharks for Green's birthday: "Now…. let's go dive with Great Whites for the first of many crazy adventures together. (What the f--- was I thinking)."

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Green has been dating Burgess since late last year after parting ways with wife Megan Fox, with whom he shares sons Journey River, 4½, Bodhi Ransom, 7, and Noah Shannon, 8½.

Since the split, Fox has moved on with Machine Gun Kelly, whom she met on the set of Midnight in the Switchgrass.

Green previously spoke about how he and Fox are handling introducing new partners to their kids, saying on an episode of the Hollywood Raw podcast, "I think the rule most people follow is you don't want to introduce someone to your kids as somebody you're interested in or that you have a relationship with until it's a very established relationship, and something that you're taking very seriously, because you don't want people coming in and out of kids' lives."

"It has to be done in a responsible way," he added. "We've talked about being as responsible as we can with the kids. We want to make this a positive experience as possible."