In the snap, the young girl wears a baby blue dress with a white bow in her hair. She has gorgeous ginger hair, similar to her father Harry and older brother Archie.
Little Lilibet looks so pretty in her first birthday photo
The picture was taken by close family friend and guest, Misan Harriman, who attended a casual, intimate backyard picnic at Frogmore Cottage for Lilibet’s special day.
Misan shared another photograph on his own Instagram account which showed Meghan and Lili smiling happily alongside his wife and their two kids.
Meghan and her friend Misan celebrate Lili's birthday
Captioning the snap he wrote: "It was such a privilege to celebrate the 1st birthday of Lilibet with my family and hers! Joy and face painting all around."
Baker Claire Ptak from East London’s Violet Bakery created a special cake for Lilibet; Ptak was also responsible for creating The Duke and Duchess’s wedding cake in 2018.
WATCH: Why Harry and Meghan kept a low profile in London
In a statement, the Duke and Duchess of Sussex shared that they "remain incredibly touched by the countless birthday wishes for their daughter, Lilibet Diana Mountbatten-Windsor, and were amazed to learn that people around the world made donations amounting to over $100K to the World Central Kitchen (WCK) in her honor".
The picture comes after Harry and Meghan made a spectacular return to the UK and along with Lili, brought their son Archie, three.
Although the Sussexes didn't attend all the events on offer across the weekend, they did make a spectacular appearance at the Trooping the Colour ceremony on Thursday where they were snapped playfully shh-ing younger members of the royal family including Isla Phillips and Mia Tindall.
Despite not appearing on the balcony for the celebration, the couple had a spectacular view of the event from the Duke of Wellington's former office.
They also appeared at the ceremony at St.Paul'shederal on Friday but did not attend the fabulous Party at the Palace the following day which was hosted for Her Majesty on Saturday evening.
The family of four has since touched back down in Santa Barbara, California, on Sunday, having spent four days in the UK for the Queen's Platinum Jubilee.
The couple were pictured driving home from the airport, but left behind some of their belongings, which were handled by airport staff - and royal fans got a sneak peek at some of the things they brought back from Winsdor, where they stayed during their time in England.
In pictures of them getting off their private jet, several items, including a swing and a wooden high chair, were seen being offloaded from Sussex's private jet, which left the UK as the final Pageant procession took place for the Queen's Jubilee.
The wooden swing could be a thoughtful gift from grandad Prince Charles. Back in 2011, he notably gave a similar gift to Prince William and Kate as a wedding present.
The gift had "William and Catherine" etched into the front and has been spotted in previous birthday portraits of Prince George.
Princess Eugenie is also in possession of a similar swing which has been spotted by royal fans in her back garden and, like William and Kate, the apparatus has her name engraved at the front too.
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