The animal caretaker, 22, took to Instagram on Tuesday to reflect on the moment she learned that she was a mother-to-be.
Alongside her story, Irwin shared a photo of herself and her hubby, Chandler Powell, cuddling up with their dog Piggy.
"Discovering that I was going to become a mother will forever be a moment where time stood still," she began in the caption. "I took a test and ran into the kitchen where Chandler was making us tea. He didn’t hear me come in so I speechlessly watched him pouring the water into my most loved hedgehog mug. This news would change the course of our future in the best way."
Next, the "Dancing with the Stars" alum said she began to cry "tears of pure joy" as she revealed the news to Powell.
"We were beaming while our adorable puppy Piggy sat on our feet wondering what was going on. It reminded me of just how perceptive animals are," she continued. "We sat together with tea talking about the future and how we were going to share such wonderful, life changing news with the people that we love. In that short span of time the gorgeous baby I'm carrying became the most important part of our lives."
Irwin concluded: "It is such a blessing knowing that this tiny person has chosen us as parents. Our baby Wildlife Warrior is going to be so very loved by our families and entire Australia Zoo team. I can’t wait to find out what this amazing new soul loves in life, and experience the world all over again through their eyes."
"Baby Wildlife Warrior due 2021. Chandler and I are proud to announce that we’re expecting!" Irwin wrote in her announcement alongside a picture of the happy couple holding up a baby-sized zoo uniform. "It’s an honor to share this special moment in our lives with you. Though I’m still in my first trimester, we really want you to be part of our journey from the beginning of this new life chapter."
She added: "We couldn’t wait to share the news as this beautiful little being has become the most important part of our lives. Your support means the world to us. Please let me know your best advice and send good vibes & prayers to our little sweetheart. Love & light."