The photo showed Jessica’s 2-year-old daughter Maxwell driving a pink toy car and her 11-month-old son Ace driving a darker pink toy fire truck.
The singer shared the snap with the caption: 'Ace and Maxi looking like twins! And yes, they share pink cars.’
Jessica’s two children are clearly the spitting image of their famous mum with their blonde hair and pink pouts.
The 33-year-old star is due to wed husband, NFL player Eric Johnson, later this year.
She recently told US’s Today Show that her wedding day ‘will definitely be extravagant.’
Jessica has been showing of her newly slim figure after shedding her baby weight over the course of the past year.
She revealed that she felt insecure of her body following the birth of son Ace last year.
She told ABC’s Good Morning America: ‘I was so insecure. I couldn't even believe what I weighed.’
I don't think that I ever expected myself to see the numbers that I have seen on the scale.'
Shockingly, Jess was criticised for her weight gain during her first pregnancy, which made her anxious about gaining weight again.
‘I knew that I would be gaining back the weight so I didn't really think about it that much,’ she said. ‘I went on walks and I worked out throughout my second pregnancy.’