The Princess of Wales has said that "faces are a baby’s best toy" after sharing an intimate photograph of herself as a child.
The image, taken by her mother Carole Middleton and showing Catherine touching her father's face, was released for the Princess's early years campaign Shaping Us, a long-term project to raise awareness about children's upbringing.
She called on others to share their own baby photos to help raise awareness of the importance of the first five years of a child's life - a call that was heeded by celebrities in their droves.
In a post on Twitter, the Princess wrote: "On Tuesday we launched #ShapingUs to raise awareness of the vital role our early years play in shaping the rest of our lives.
"This weekend, we’d love for you all to spend time with your friends, families, colleagues and communities talking about your early childhoods and how they’ve shaped your lives.
"I hope you’ll also consider joining me in sharing a picture of yourselves before your fifth birthday to help with those conversations and to share some smiles and memories too."
The Three Lions captain Harry Kane became the first celebrity to follow Catherine by posting a childhood picture of him aged five with his "right foot ready to go".
Jamie Oliver was next to join in, with his official team sharing a picture of the restaurateur aged five dressed in brown corduroy trousers and roller skates.
Radio presenter Zoe Ball posted an image of herself aged two with her father, "perched upon a giant sheep toy" which she said was a present from her godfather, Tony.
Ms Ball added that early childhood "shapes the rest of our lives", from pregnancy to the age of five, and encouraged followers to also post an image of themselves in early childhood in support of the campaign.
BBC Strictly Come Dancing host Tess Daly also shared a photo of herself aged four with her younger sister Karen, walking in the Peak District where they grew up, to support the campaign.
The social media initiative is the latest release for the Princess's campaign Shaping Us, a long-term project to raise awareness about the importance of a child’s first five years of life.
In a video released on Thursday the Princess discussed mental health with Roman Kemp, the Capital FM presenter, saying "it's really important to stress we can’t take a fatalistic outlook on this".
"For those who haven’t had happy childhoods, they can still go on to happy, healthy lives with the right support and the right interventions as well," she told the presenter.
"This is why it is essential, to not only understand the unique importance of our earliest years, but to know what we can all do to help raise future generations of happy, healthy adults."
Kemp is taking part as one of the campaign’s "champions", the celebrity supporters helping to spread the message to their respective audiences and generate awareness, particularly among the younger generation.
The Princess, wearing a sheepskin coat, roll-neck jumper and gloves, told the radio host that her Shaping Us campaign "isn’t just about raising kids".
"It’s about shaping our futures and shaping not only the adults we become, but shaping our society, creating a happier, healthier, more nurturing world for us all to live in as well," she said.
On Monday, the Princess outlined her vision for a major new public awareness campaign about the importance of early childhood saying that it is "essential" to understand how "we lay the foundations and building blocks for life".
The Princess, accompanied by the Prince of Wales, attended a launch event at Bafta, where she introduced the long-term campaign that will form the foundation of her future work.
"It is when we learn to understand ourselves, understand others and understand the world in which we live," the Princess added at the event.