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

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

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

“It can be hard to celebrate the milestones when there’s someone missing,” Irwin wrote.

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

The wildlife warrior thanked his family and said he felt lucky to be surrounded by so many amazing people while he got ready to celebrate his special day.

He also took the chance to look at photos of his dad on his 21st and the resemblance was striking.

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

Steve Irwin on his 21st birthday. Credit: Instagram

Bindi Irwin supported her brother writing: “Dad is so 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 incredible adventure on the horizon. Love you so much and beyond proud of you,” she wrote.

This week he choked back tears as he spoke about his late father, after his wax figure was unveiled at Madame Tussauds in Sydney.

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

“It was the first time I’d ever got to see my dad’s wax figure. I’d seen pictures of it, but I’d never seen it in real life, and I was actually, I was overcome with emotion and I didn’t think that 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, kind of just standing there, it was a lot to take in.”