Terri Irwin Talks Becoming a Grandmother in New Crikey! It's a Baby! Clip: An 'Indescribable Time'

Terri Irwin is finding a new level of love as a grandparent.

In a clip from the upcoming discovery+ special Crikey! It's a Baby! shared exclusively with PEOPLE, Terri, 56, shares her excitement about becoming a grandmother as her daughter Bindi Irwin prepared to welcome a baby girl of her own.

"It's so exciting to be a mom because all of a sudden you get, like, a do-over. You get to experience the world again through the eyes of a child," says Terri, who also shares son Robert, 17, with her late husband Steve Irwin.

The sneak peek also shows a 2003 clip of a pregnant Terri telling Bindi that she had a little brother on the way, sweetly joking at the time that her mom's belly "can't possibly" get bigger. "I don't want a boy!" says little Bindi with a smile.

Terri, while awaiting the arrival of Grace Warrior Irwin Powell — whom Bindi and husband Chandler Powell welcomed on March 25 — said becoming a grandma is "the most marvelous, wonderful, indescribable time."

"Mom is just amazing," says Bindi. "I won the lottery when it came to moms, I really did. And I know that she is going to be the most extraordinary grandmother as well."

Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday.

discovery+/Australia Zoo

discovery+/Australia Zoo

RELATED: Robert Irwin 'Can't Wait' for Niece Grace Warrior, 3 Weeks, to 'Grow Up and Take on the World'

Bindi and Chandler also discuss Terri's "cute" grandmother nickname, Bunny, with the new dad saying with a smile, "It'll just melt your heart every single time our daughter says Bunny."

"It will actually," says Bindi, "I'm really looking forward to that."

The all-new discovery+ special chronicles Terri and Robert helping Bindi and Chandler during her pregnancy while the family continues their wildlife conservation efforts. The special will feature poignant and intimate moments leading up to the birth of Bindi and Chandler's daughter, whom discovery+ audiences will meet in the special.

Crikey! It's a Baby! streams on discovery+ beginning Sunday, April 25.