Robert Irwin turned 21 and paid tribute to his dad and Aussie legend Steve Irwin in a heartfelt post

It’s Robert Irwin’s 21st birthday today and he took the opportunity to pay tribute to his father and Aussie legend Steve Irwin in a heartfelt post.

The young man lost his father in 2006 when he was only two years old.

“It can be difficult to celebrate milestones when someone is missing,” Irwin writes.

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“But I will carry his memory and passion with me into this new chapter of life.”

The wildlife warrior thanked his family and said he feels lucky to be surrounded by so many amazing people as he prepares to celebrate his special day.

He also took the opportunity to look at pictures of his father on his 21st day and the resemblance was striking.

“I was going through the archives a few days ago and found these photos of my dad on his 21st.”

Bindi Irwin supported her brother, writing: “Daddy is proud of you.”

She also wished him a happy birthday in her own post, sharing a series of heart-warming images.

HAPPY 21ST BIRTHDAY, @robertirwinphotography! Best brother, best uncle, best friend. Here’s to every amazing adventure on the horizon. I love you so much and I’m proud of you,” she wrote.

He choked back tears this week as he spoke about his late father after his wax figure was unveiled at Sydney’s Madame Tussauds.

Irwin is the youngest Australian to be honored with a wax figure at Madame Tussauds.

“It was the first time I saw the wax figure of my father. I had seen pictures of him but I had never seen him in real life and I was actually, I was overcome with emotion and I didn’t think this was going to happen,” he told Sunrise.

“I was actually quite emotional seeing it, you know. Dad for the last, well, 17 years of my life has been pictures and video and to actually see him just standing there was a lot to take in.’