Rossi shared a baby bump photo and more details in the caption. The new mom is recovering after giving birth via C-section.
"God is Great!! Skylar Gray Smiley arrived safely into this world today! Most amazing & emotional day of my life! I am doing good as well of course I have some pain from the c-section, but it was all so worth it!" Rossi wrote.
"Details and pics coming soon! But for now just focusing on Sky and taking good care of her. Thank you all for your prayers and love today! Love you guys!" she added.
Former "Flipping Out" star Jenni Pulos was among those to congratulate Rossi in the comments.
"Miracle girl... She's here! Congratulations," she wrote, adding three heart emojis.
Rossi had announced in a post Tuesday she would undergo a scheduled C-section Wednesday.
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"I had a really really tough day yesterday because of having to make a super hard decision after my doctors appt. but after a lot of contemplation, crying, struggling, (and based on the medical pros and cons) the Doctor, Slade and I have decided a c-section is going to be the safest thing for me and baby tomorrow," the star wrote.
"When you have this vision of how you want your labor and delivery to go and it doesn't turn out the way you imagined, there is this sadness and internal struggle," she said.
"So after crying it out, and being sad about not having a 'vaginal birth' yesterday, I asked God to give me a sign that this is the best decision, and he did!"
Rossi announced her pregnancy in December after conceiving via in vitro fertilization.
She reflected on her pregnancy in a post last week, calling it one of the "most incredible experiences" of her life.
"It's wild to think I will have this little life outside of me now," the star wrote.
"Of course I'm so excited to meet her but also feeling emotions of sadness at the same time. Please tell me I'm not alone in this sentiment?"
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