"The girls are super psyched after meeting my old mate and 2008 Supercar co-driver @michael.patrizi at his Gold Coast @patrizicorse karting factory. Lots of fun toys in there!" Grant captioned the post.
The TV star went on to reveal that Sailor and Scout have already been showing signs that they're keen to follow in their father's footsteps.
"The Denyer girls have been chucking buggies and bikes sideways around the house for ages now and it seems it’s possibly time to bite the bullet and get them into proper karts and into circuit racing," Grant wrote.
"Poor Scout is so tiny, we had to find the smallest thing we could possibly manufacture just so she could reach. But she’s got plenty of fire in her! She’ll be a demon behind the wheel I think."
Grant clarified that he was not forcing his girls into any career path, he was simply admiring their gusto, writing, "I’m not pushing them, it’s their call but who knows where this will go.
"But I do love their enthusiasm to try!"
Grant's followers were equally as thrilled about Sailor and Scout's newfound interest, albeit slightly scared for their mum Chezzi Denyer.
"Love this!!! Karting was a massive part of my childhood, it built lifelong friendships. Hope they love it! 🙌," one fan wrote.
"Living in the fast lane girls. 🏎🏎," another penned.
"Just as well Chezzi is blonde...you won't see her grey hairs from all the stress haha," a concerned user added.
WATCH: Grant Denyer how he first started dating wife Chezzi (Story continues after video)
Back in 2017, Grant was the victim of a near-fatal car crash while racing.
At the time, the presenter assured his fans he would be back behind the wheel as he wanted to be a good role model for his kids.
"I'll be back in the race car for sure. You don't want your last experience to be a bad one … and what lesson would I be teaching my kids if you have a knock and then you give up?" the now-43-year-old told The Daily Telegraph.
Grant, who welcomed his third child - a daughter called Sunday in February, also gushed over his wife's support through the whole ordeal, telling the publication, "Cheryl completely left the decision to me which was wonderfully gracious. She comes to the track all the time with the kids."
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