Royal fans were delighted when the Princess of Wales shared an intimate family photograph of her as a baby, happily smiling and reaching to grab her father's face.
The words "faces are a baby’s best toy" came with the treasured image along with the description “with Dad, by Mum” after she released the snap as part of her new Shaping Us campaign.
Kate, 41, who was born at the Royal Berkshire Hospital in Reading, is just a baby wearing a summer dress in the photograph with her father Michael Middleton that was taken by her mother Carole.
And ever since she posted it, fans were quick to point out just how much of a resemblance there is between Kate and her youngest son four-year-old Prince Louis.
On Instagram, one fan even remarked how she and Louis at the same age looked like twins, while another thought the young snap of Kate was actually Louis.
And it seems the mother and son resemblance is something that has been pointed out to Kate in the past - and has become an in-joke as her other children Prince George and Princess Charlotte look more similar to their father Prince William.
According to a friend of Kate, this has led to her joking that little Louis is the only one out of the three kids that actually looks like her.
The friend previously told PEOPLE: "Everyone always comments on how Louis is the spitting image of Kate.
"She loves it and thinks it's very sweet — she often jokes that he's the only one of her kids who actually looks like her!"
Kate launched her Shaping Us campaign on Tuesday to raise awareness of the vital role our early years play in shaping the rest of our lives.
She has also said her early years campaign goes beyond "raising kids" and is also about "shaping our society" and creating a "more nurturing world".
Speaking to radio presenter Roman Kemp, Kate said highlighting the importance of early childhood was not about putting "extra pressure" on parents, but saying they needed "help reprioritising family life".
The Shaping Us initiative is a campaign described as her "life’s work" and is aimed at raising the profile of the crucial period of a child’s development, from pregnancy to the age of five.
The campaign has the support of a number of famous people, including rapper Professor Green, presenter Fearne Cotton, former Saturdays singer Rochelle Humes and Lionesses’ captain Leah Williamson.
Kate's comments to Kemp were filmed last month in the grounds of the Hertfordshire home of the Capital FM presenter's parents, Spandau Ballet star Martin Kemp and singer Shirlie Holliman.
She told the host of Capital’s breakfast show: "This isn’t just about raising kids.
"It's about shaping our futures, shaping our society, creating a happier, healthier, more nurturing world for us all to live in."
