Terri Irwin Says Late Husband Steve 'Would Be So Proud' of Daughter Bindi Becoming a Mom

Bindi Irwin Expecting First Child with Husband Chandler Powell

"It’s an honour to share this special moment in our lives with you," wrote Bindi Irwin on Instagram

Terri Irwin couldn't be happier about daughter Bindi expanding her family — and she knows Steve would be too.

On Tuesday morning, the 22-year-old Crikey! It’s the Irwins star revealed on Instagram that she's pregnant with her first child with husband Chandler Powell, whom she married in March. "Chandler and I are proud to announce that we’re expecting!" she wrote in her announcement.

Terri, 56, tweeted in response, "This is the best day ever! I am over the moon to announce that @BindiIrwin and @chandlerpowell9 are going to have a baby! Words cannot express the love that is filling my heart."

"While I wish that Steve was here to share this beautiful moment, I know that he would be so proud," added Terri, who is also mom to 16-year-old son Robert.

Steve (perhaps better known as the Crocodile Hunter) was killed during a diving expedition off the coast of Australia in September 2006. He was 44. On her wedding day, March 25, Bindi was sure to honor her late father in her ceremony.

Terri Irwin Twitter Terri Irwin, Bindi Irwin, Chandler Powell

“Where we got married was such a special place to dad,” Bindi previously told PEOPLE of the garden at the Australia Zoo. “It’s a beautiful little area where he had filmed for many years. It felt really wonderful and just meant to be.”

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RELATED GALLERY: 20 Throwback Photos of Bindi Irwin With Her 'Superhero' Dad, the Late Steve Irwin

“We had dad’s picture with his dog Sui blown up on an easel,” added Bindi. “So mom and Robert were standing right next to dad as we exchanged vows. We had a candle-lighting ceremony for him, and it really felt like he was there with us. It was a lovely moment of peace and happiness.”

In her pregnancy announcement on Instagram, Bindi dubbed her "beautiful little being" her "Baby Wildlife Warrior."

"It’s an honour to share this special moment in our lives with you," Irwin captioned the photo early Tuesday, which showed herself smiling alongside Powell, 23, as they held a tiny Australia Zoo uniform fitted for the baby-on-the-way.

RELATED: The Late Steve Irwin and Son Robert's Sweetest Twinning Moments

Newspix/Getty Images Steve and Terri Irwin with a young Bindi in 2002

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"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 continued. "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. ❤️"

Powell commented on his wife's post, writing, "You’re going to be the best mother ❤️"