Bindi and Robert Irwin mark parents' 31st wedding anniversary

The Irwin kids are honoring what would have been their parents' 31st wedding anniversary.

Bindi and Robert Irwin took to their respective Instagram feeds on Sunday to share tributes to their mom Terri Irwin, 58, and their late father Steve Irwin on their special day.

"A love like this is eternal. Happy Anniversary to my extraordinary parents ❤️," Bindi Irwin, 24, wrote alongside a photo of her parents posing for the camera next to a vehicle, with her dad's arm draped across her mom's shoulder.

A post shared by Bindi Irwin (@bindisueirwin)

"Happy wedding anniversary Mum and Dad. Forever my biggest inspirations ❤️," Robert Irwin, 19, wrote alongside a close-up photo of his parents cuddling with each other and some furry animal friends.

A post shared by Robert Irwin (@robertirwinphotography)

Terri and Steve Irwin married on June 4, 1992 in Oregon, Terri Irwin's home state.

Steve Irwin died in September 2006 when he was stabbed by a stingray's barb while filming off the coast of Australia. He was 44.

The "Crocodile Hunter" star's family have continued to honor him at every turn in the years since his death, keeping his legacy of animal conservation alive through the Australia Zoo.