"Don’t even think about it little ladies @willowstefanovic 😂😂," the shoe designer wrote.
But while Jasmine had her reservations, another famous face was all for the idea. Former Home & Away star Christie Hayes jokingly implored the toddler to swipe some cash from her dad, writing, "Get your Dads credit card, Harper! 😂😍 ❤️"
While Karl joked about his youngest child hitting the town with his older daughter Willow, otherwise known as Ava, the teenager herself is not yet 18. In fact, she not long celebrated her sweet 16th. And the occasion brought with it an important milestone for the teenager.
After turning 16, the budding model wasted no time engaging in the classic teenage ritual of learning how to drive, getting her L's quick smart as her step-mum Jasmine watched on proud, albeit slightly scared.
Heading to her Instagram stories at the time, the shoe designer Jasmine shared a sweet snap of her 16-year-old standing next to a car, a brand new pair of L plates in hand.
"Got her L's @willowstefanovic" Jasmine captioned the sweet image.
The following story actually documented Ava behind the wheel of a car with a caption that was slightly less calm than the first.
"To say this was scary is an understatement." the step-mum wrote.
WATCH: Karl Stefanovic's daughter scores new gig at Today
On Ava's actual birthday, Jasmine shared a sweet tribute to her step-daughter.
“Happy Sweet 16th beautiful girl,” Jasmine captioned a carousel of snaps, which included a snap of the pair striking a pose together, as well as Ava holding a birthday cake.
Ava is the second eldest daughter of the couple. Jasmine is also a step-mum to Karl's kids Jackson, 22, and River, 14. Harper is the only child the couple share together.
But rumour has it the family of six could be adding another baby to the mix.
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