Robert Irwin has broken down as he shared one of the final things he father ever said to him.

Steve Irwin died on September 4, 2006, after being pierced in the chest by a short-tail stingray barb while filming in the Great Barrier Reef with Philippe Cousteau Jr.

The 21-year-old was just two years old when his dad passed away, but he saw a message Steve left for him in a video.

Appearing on the podcast The Viall Files this week, Robert was moved to tears as he explained how moving the experience of seeing the clip was.

‘For me watching that, it’s like he gave me this gift –  it’s there, it’s material, it’s in writing,’ he said tearfully.

‘I’m watching him looking through the camera and telling me, “I’m not always gonna be here.”‘

The video showed Steve explaining how he was building a legacy to leave to his children.

Robert explained that his father told him that he was ‘creating something that you can continue and that’s what I want you to do’.

‘He said, “My whole mission is to leave a legacy that my kids can continue.” He said that years before he passed,’ Robert said.

Robert had his fans in tears during his appearance on Dancing with the Stars US this week.

The theme of the evening was Dedications, and Robert and his dance partner Witney Carson chose an emotional dance to the Phil Collins track You’ll Be In My Heart, which he dedicated to his mother, Terri, 61.

Before taking to the stage with Witney, Robert was already overcome with emotion, speaking about his mother to camera.

‘She’s an absolute hero to me, because I was two when I lost dad [wildlife warrior Steve Irwin],’ Robert said, struggling to contain his emotion.

‘As I got older, [I] started to realise just how hard it would have been for her to be there for us, and all the while continue dad’s legacy that her and dad built together.’

Robert added: ‘I’ve never been able to capture the feeling of gratitude I feel for her.’

‘At every milestone, when I just wish that my dad was there, she was there. That was enough.’

The routine went off without a hitch before Robert surprised everyone with a cameo from Terri in the final moments of the dance.

As they concluded their dance, Robert broke down in tears as he lovingly hugged Terri in front of an adoring crowd.

Terri, overcome with emotion herself, also fought back tears following the performance.

‘I love him so much. I’m so blessed to be his mum,’ she said, to which Robert replied: ‘This dance is for my mum, and for all the mums who don’t get the recognition they deserve. If you can, call your mum and tell her you love her.’