Jack Osbourne and Fiancée Aree Gearhart Expecting First Child Together

On Monday, the engaged couple revealed on Instagram that they are expecting their first child together, sharing that their new addition will arrive this summer.

The baby will be Jack's fourth as the reality star shares three daughters with ex-wife Lisa Stelly: Pearl, 9, Andy, 6, and Minnie, 4. However, this will mark the first child for Aree.

Sharing a sweet photo of himself holding Aree's baby bump, above, Jack, 36, wrote, "Exciting news!!! @seecreature and I are expecting a baby in the summer! Baby #4 here we come!"

Aree, 31, an interior designer, also posted the exciting news on her Instagram profile, resharing the photo Jack posted. Aree also revealed that Monday, the day in which she and Jack announced her pregnancy, was also her birthday.

"today is my birthday, but my gift doesn't arrive till summer ;-)," she captioned her post. "new member of our tribe coming summer 2022."

Kelly Osbourne, Jack's older sister and Aree's future sister-in-law, commented on Aree's post, writing, "You're a nimbly bimbly kitty cat who's heart is pure and true. Cause you’re a nimbly bimbly kitty cat who's now eating for 2!!!!!!!!!!! Yes you're a nimbly bimbly kitty cat and that’s why I love yooooooou……. Outside of you and jack there is no one more excited for this baby and you know why!!!!!!!!"

She also posted a birthday tribute to Aree on her Instagram Stories. Alongside a photo of herself and Aree, Kelley wrote, "@SEECREATURE YOU MAY BE MY BROTHERS FIANCEE BUT YOU'RE MY BEST FRIEND BIIIIIIITCH! HAPPY BIRTHDAY ... I WOVE YOOOOOOOOU!" Kelly also added a GIF that read: "HAPPY, HAPPIER, HAPPIEST, BIRTHDAY!"

Meanwhile, Sharon Osbourne, took to Instagram to offer her congratulations to her son and future daughter-in-law.

"I couldn't be more excited about grand-baby 👶🏻#4!!!," she captioned her post, in which she shared the same photo Jack and Aree posted. "Congratulations @jackosbourne & @seecreature !"

Jack and Aree announced their engagement in December, sharing a photo of themselves posing together outside amidst a gorgeous, snow-filled scene. As shown in the shot, below, Aree's stunning engagement ring was on full display.

"Today I asked the most beautiful and loving woman I've ever met to marry me. She said yes!!," Jack captioned his post. "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," he added. "Her step-mom skills make my heart so full. I couldn't be happier [than] I am right now."

Meanwhile, Aree wrote, "today my best friend asked me to marry him in a magical winter wonderland. 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."

Their engagement came after two years of dating. According to PEOPLE, Jack and Aree first revealed their romance when they attended the 2019 American Music Awards together and were seen holding hands.