"You're going to fill in next week as a guest weatherman!" host Natalie Barr exclaimed to the 18-year-old. "Tell us about that!"
"I am," Robert said with a laugh. "All I can say is: Sam Mac, I am coming for ya! I'm excited, it's gonna be good fun guys!"
"We cannot wait to see you then!" David 'Kochie' Koch added.
Elsewhere in the chat, Robert told the hosts about his father's passion for photography, something that he also loves.
"A lot of people don't realise Dad was an incredibly passionate photographer," he told the hosts. "He was amazing behind the camera, just as much as he was in front of the camera, of course.
"And I think part of my love of photography is genetic."
While he loves taking photos of animals, Nat asked whether he also enjoys taking photos of his niece Grace.
"She is wildlife in itself, she is pretty wild, she is just going a hundred miles an hour, little Grace," he said with a laugh. "She's the best, I'm the luckiest uncle on the planet, I just think she's wonderful.
"So, getting to follow her around and take photos of her and be part of her life as her uncle, it's so much fun and it's such a wonderful time for the whole family. She's great."
Robert reveals Steve Irwin's alter ego
In an interview with Stellar, Robert shared that his mum Terri and sister Bindi often tease him for his trendy wardrobe, adding that while he loves experimenting with fashion, he feels most at home in his Australia Zoo khakis.
"My dad wasn’t exactly a fashion icon, but he was iconic just in the fact that he made khaki cool," he told the publication.
Robert adds that wearing the uniform allows him to feel a sense of connection to his father, saying it helps him feel a "sense of purpose".
He adds that he's not afraid to take risks with fashion because it's when it's wearing something a little out of the ordinary that people are more likely to not recognise him – a tip he picked up from Steve.
"He had an alter ego called Glenn Glamour," Robert shared. "He would put in false teeth, a wig, this ridiculous multicoloured trench coat, the weirdest pants and really sketchy sneakers.
"And that’s how he would get around the zoo and no one would notice him because he was just wearing the most ridiculous thing. So, ironically, the more exciting and experimental you are with your fashion, the less people will recognise you – at least for me."
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