Bindi Irwin welcomed her first baby, daughter Grace Warrior Irwin, on Thursday

Terri Irwin is beyond proud of her family's next generation.

The Crikey! It's the Irwins star, 56, congratulated her daughter Bindi and her son-in-law Chandler Powell on welcoming their first baby, daughter Grace Warrior Irwin, writing on Twitter Friday that her late husband Steve would have been "beyond proud" of them.

"Love is not a big enough word," says Terri. "My heart is so incredibly happy. And I know that Steve would be beyond proud."

She added, "Grace is the next generation to continue his mission and message of conservation. She chose her parents wisely. Bindi and Chandler are already the best parents ever!"

"We love you beyond words," Bindi, 22, replied to her mom.

For more on Bindi Irwin's baby news, listen below to the episode of PEOPLE Every Day!

Steve, a.k.a. the Crocodile Hunter, was killed during a diving expedition off the coast of Australia in September 2006 at age 44. Steve and Terri share son Robert, 17, in addition to Bindi.

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Last month, Bindi explained to The Bump why Terri chose her grandmother nickname to be Bunny.

"My extraordinary mama is my best friend and I know that she is going to be such an amazing grandmother," she said at the time. "We spent a long time searching for grandma names that also had an animal link. We decided that she's going to be called 'Bunny.' "

"When she was growing up in Oregon her neighbor down the street was always called 'Bunny.' It only just dawned on us that it wasn't her name but rather what everyone called her since she was a grandmother figure to the entire neighborhood," she added.

Bindi Irwin, Steve Irwin
Steve and Terri Irwin with a young Bindi in 2002
| Credit: Newspix/Getty Images

On Friday morning, Bindi shared details about welcoming her baby girl in a loving Instagram post, featuring a photo of her and Chandler holding little Grace and another of a baby blue onesie with a koala bear on the front.

"March 25, 2021. Celebrating the two loves of my life. Happy first wedding anniversary to my sweetheart husband and day of birth to our beautiful daughter. ❤️ Grace Warrior Irwin Powell. Our graceful warrior is the most beautiful light. Grace is named after my great-grandmother, and relatives in Chandler's family dating back to the 1700s," she explained in her heartfelt caption.

"Her middle names, Warrior Irwin, are a tribute to my dad and his legacy as the most incredible Wildlife Warrior. Her last name is Powell and she already has such a kind soul just like her dad. There are no words to describe the infinite amount of love in our hearts for our sweet baby girl. She chose the perfect day to be born and we feel tremendously blessed," she added.