The Princess of Wales was accompanied by her husband ahead of the launch of her Early Years campaign, but joked that Prince William was unlikely to buy her flowers for Valentine's Day.
Kate, 41, made the quip during a tour of Kirkgate Market in Leeds on Tuesday, as she marked the start of her landmark project, Shaping Us, which aims to raise awareness of the first five years of a child's life.
WATCH: Princess Kate reveals why her early years project is so crucial
When Kate stopped at florist Neil Ashcroft's business, she admired his display of flowers and with Valentine's Day just a fortnight away he said: "William will be buying you some roses?" and then cheekily offered her a discount on the blooms.
After presenting her with a bouquet of hyacinths he claimed were her favourite flowers, the stall holder said: "I suggested William will be buying her roses and she said, 'I don't think he will do'".
RELATED: Royal fans all say same thing as Princess Kate makes special appearance with Prince William
In 2012, the then Duke and Duchess of Cambridge had to spend their first Valentine's Day as a married couple apart.
William was deployed to the Falkland Islands for six weeks in his role as a RAF search and rescue pilot at that time. And that meant missing out on the annual holiday with his wife of ten months.
Kate toured Kirkgate Market in Leeds
But William made sure to treat Kate on the day, as she revealed when she stepped out for solo engagements in Liverpool.
When one little boy told the Duchess he was sorry that William couldn't be with her on Valentine's Day, Kate told him: "Do you know where he is, Janson?
"He's in the Falklands but he's sent me a card this morning."
Jaqson's mother also revealed at the time that the Duchess said she received a bouquet of flowers from her husband as well as a card.
William and Kate, who are parents to Prince George, Princess Charlotte and Prince Louis, will celebrate their 12th wedding anniversary this April.
Kate has launched her Shaping Us campaign
In a video message released to highlight the Shaping Us campaign, the Princess said: "Our early childhood, the time from pregnancy to the age of five, fundamentally shapes the rest of our lives.
"But as a society, we currently spend much more of our time and energy on later life.
"Today, the Royal Foundation Centre for Early Childhood is launching a new campaign, Shaping Us, to raise awareness of the life-changing impact we can have when we build a supportive, nurturing world around children and those who care for them.
"Because by focusing our collective time, energy and resources on these most preventative years, we can make a huge difference to the physical and mental health and happiness of generations to come."
LISTEN: King Charles - The Man Under The Crown