Bindi Irwin gets engaged at Australia Zoo on her 21st birthday: 'I said yes and forever'

Bindi Irwin, the daughter of the late TV zookeeper Steve Irwin who has become a famous animal expert in her own right, was enjoying a pretty nice 21st birthday: She spent the day at her favorite place, the Australia Zoo, surrounded by friends, family and animals.

And then her longtime boyfriend proposed.

"On my birthday I said ‘yes’ and ‘forever’ to the love of my life," Irwin wrote in an Instagram post Wednesday. "Chandler, close to 6 years ago I fell in love with you and every day since has been a whirlwind of adventure and true happiness. I’m so looking forward to spending our forever together as your wife. Here’s to a lifetime of friendship, purpose and unconditional love. — Now let’s get married already!"

The older of the two Irwin children, Bindi met Chandler Powell, a Florida native, in 2013 when he was visiting Australia for a wakeboarding competition, he revealed in 2015 when Irwin was on "Dancing with the Stars." Irwin gave him a tour of the Australia Zoo.

Irwin already knew she'd be participating in a photo shoot at the zoo to celebrate her birthday, Powell said in an interview with People on Thursday — what she didn't know was that Powell was planning to get down on one knee right before it started.

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"I Immediately fell head over heels for her kind and thoughtful heart that radiates so much light," Powell wrote in his own Instagram post. "Proposing in her very favorite place in the zoo, surrounded by animals, seemed like the perfect way to embark on this incredible new chapter in our lives. Bee, I love you more than anything in this world and I always will. Happy Birthday."

Irwin told People she's grateful to find a person with qualities that remind her of her father, who died in 2006 at age 44 from a stingray attack while filming.

“He loves wildlife and conservation and he has this strength," she said of Powell. "Which is necessary when you’re jumping on crocs."

Irwin's mother, Terri, called Wednesday the "best day ever."

"Chandler asked and beautiful @BindiIrwin said yes," she tweeted. "I am so very happy, and I know Steve would be too."

The Australia Zoo sent the couple well-wishes on Twitter: "Crikey! Chandler proposed on beautiful Bindi's birthday right here at #AustraliaZoo. Such a wonderful time for our entire Australia Zoo family. We love them both so much."

Animal Planet also shared its "excitement for this beautiful couple... Wishing you a lifetime of love happiness."

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This article originally appeared on USA TODAY: Bindi Irwin, Steve Irwin's daughter, gets engaged on 21st birthday