Jack Osbourne and Fiancée Aree Gearhart Expecting First Baby Together: 'New Member of Our Tribe'

Jack Osbourne is going to be a dad again!

The Fright Club star, 36, announced on Instagram Tuesday that he and fiancée Aree Gearhart are expecting their first baby together. This will be Gearthart's first child while Osbourne is already dad to Pearl Clementine, 9, Andy Rose, 6, and Minnie Theodora, 4, with ex-wife Lisa Stelly.

"Exciting news!!! @seecreature and I are expecting a baby in the summer! Baby #4 here we come!" Osbourne wrote alongside a photo himself cradling Gearhart's growing baby bump.

Making the baby news even more special, the announcement was shared on Gearhart's 31st birthday. She posted the same photo on her own Instagram, adding: "Today is my birthday, but my gift doesn't arrive till summer ;-) new member of our tribe coming summer 2022."

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Osbourne and Gearhart got engaged in December 2021 after the pair dated for over two years.

"Today I asked the most beautiful and loving woman I've ever met to marry me. She said yes!!" Osbourne captioned a selfie of himself and his fiancée after popping the question. In the snap, Gearhart showed off her huge sparkler while they posed outside in their snow-covered surroundings.

"Life is a series of doors and I'm so excited to walk through this one with her. She's truly a magical being with a heart bigger than anything I could have imagined," Osbourne continued. "Her step-mom skills make my heart so full. I couldn't be happier than I am right now."

Aree Gearhart/instagram

Gearhart posted a simple snapshot of her gorgeous ring on her Instagram Story, as well as an equally touching and emotional message of her own, reposting the same picture her future husband shared.

"Today my best friend asked me to marry him in a magical winter wonderland," the interior designer sweetly captioned the photo. I'll love you forever and then some @jackosbourne. my soulmate, my adventure partner, my protector. i'm ready for forever w you + our tribe."

Aree Gearhart Instagram

RELATED: Jack Osbourne Is Engaged to Aree Gearhart: 'Couldn't Be Happier'

Osbourne's mom, Sharon, also wished the couple congratulations after the engagement on behalf of her and husband Ozzy, writing, "Ozzy and I couldn't be happier and more proud of our son Jack's engagement to Aree Gearhart. We are so blessed to have Aree as part of our family and we wish them a lifetime of love, light and happiness."

His sister Kelly also posted about the exciting news at the time, captioning a photo of her and Gearhart on her Instagram Story, "We are family." She also commented on Gearhart's photo of her and her brother, writing, "I'm so so so beyond happy!!! Now we really are sisters!!!! I love you so much. Welcome to the family!!!!"

Osbourne and Gearhart first went public with their relationship in November 2019 after they were spotted holding hands at the American Music Awards. Gearhart has been an integral part of the Osbourne family since, having gone on vacation with the group, as well as on double dates with Sharon and Ozzy.

Osbourne's divorce from his ex-wife was finalized in March 2019.