Locals walking their dogs along a Norfolk beach in August barely gave a second glance to the small sailing boat gliding past offshore.
Those who did look a little closer might have spotted a man and three young children being shown the ropes by an experienced female sailor.
But only a handful actually recognised the athletic brunette at the tiller of the dinghy, because this was the off-duty Duchess of Cambridge as few people have ever seen her – scruffy, windswept, and exuberant.
And as, over the course of a happy week, she taught her family how to sail, low-key Kate was clearly in her element.
“If you’ve ever wondered what Kate is like away from the cameras, that simple sailing trip summed it up perfectly,” says royal expert Katie Nicholl.
“It was Kate at her happiest and most natural – out on the open sea with her husband and children, relaxed, carefree, hair flowing in the wind, just having a wonderful time. That is what Kate is like off-duty.”
Katie, author of Kate: The Future Queen, goes on, “The public are used to seeing Kate looking elegant and stylish on her public engagements. She even manages to look amazing abseiling down a cliff, mountain biking or playing tennis with Emma Raducanu.
“Yet at home, relaxing behind closed doors, she’s just like any busy working mum. She is happiest in jeans and a casual sweater, hair tied back and with very little make-up on.”
Kate has the support of a stylist and hairdressers to help her don “the duchess” look before official functions.
But, like her late mother-in-law Diana, Princess of Wales, she has never let glamorous designer outfits and strict royal protocol hide her warm, natural personality.
Royal expert Duncan Larcombe says, “Kate understood from the outset that for the public to truly relate to her, they have to see she is authentic and open.
“That is why her private passions and interests drive her public duties and have influenced the patronages she has adopted.
“Of course we don’t see the exact same Kate that her husband, children and family do. But friends tell me she really isn’t that different in private. She is a warm, caring mum who loves nature, the great outdoors, sport and the simple pleasures of home. And she is, very genuinely, always thinking of others.”
Her uncle, Gary Goldsmith, agrees. He explains, “Kate was an ordinary girl, a bit of a tomboy. But at the same time she always had values. She was kind, just a lovely person.
“I think she’s quite unique. She’s as beautiful inside as out. And she knows about duty and putting others before herself. Kate is a giver, not a taker.”
Family has always come first for Kate and when she and William first began dating he quickly fell for the joys of a Middleton family weekend – long walks, a pub lunch, tea in front of the fire, then a fiercely competitive game of backgammon or Trivial Pursuit.
Back at St Andrews, Kate helped William to improve his cooking skills, although both loved – and still do – an Indian takeaway or a pizza.
They are also partial to Pringles and would munch through tin after tin while watching their favourite films and TV programmes, with Kate sipping her favourite tipple, red wine.
Kate has never had to worry about her figure as she plays so many sports. Tennis is her greatest love – and she showed off her impressive forehand when playing with the new US Open Champion in September.
She also loves hockey, cricket, athletics and volleyball and trained with an all-girl dragon boat crew in 2007.
Kate learned to sail on family holidays in the Lake District as a child and spent part of her gap year crewing in a round-the-world yacht race. She is now a patron of the sailing charity 1851 Trust.
Kate impressed William with her skiing ability on their first holiday to Klosters in 2008, and the pair both showed off their dance-floor skills at university parties.
Kate has a lovely voice and once sang in a church choir, but neither she or William are great fans of karaoke.
But there’s a first time for everything. Former Girls Aloud star Cheryl Tweedy revealed in her autobiography that “Kate confessed that she dressed up as me on her hen night, in a bodysuit and split trousers, and sang Fight For This Love”.
Although she no longer plays the flute, Kate is said to be looking forward to helping her children learn to play the recorder. And she’s already inspiring them with her love of art and photography.
Kate studied history of art at university and her dissertation was titled “Angels from Heaven: Lewis Carroll’s Photographic Interpretation of Childhood”.
Her own camera skills have improved in the past few years and her birthday portraits of the children have won praise from professionals.
They have also given the family more precious time out of the spotlight. Kate likes nothing more than to take George, Charlotte and Louis to a playground, restaurant, the cinema or the local supermarket and go unnoticed.
After her wedding, while still living in Anglesey with William, Kate would often pop to the shops without a fuss. She once tried on a wetsuit in a local surf shop and decided to buy it, only to discover she’d forgotten her purse.
“I’ll come back tomorrow,” she said, giving a name and asking the owner to reserve it for her. It was only when a protection officer popped back in with the cash that he realised who “Mrs Cambridge” was.
Duncan Larcombe says the Cambridges’ off-duty life is remarkably normal, thanks to Kate. He adds, “She is happiest when she’s got the children in the kitchen making cakes or jam, and a terrible mess, or when they are sitting around the table eating.
“But she and William also love taking them to a pub garden for a burger, where they often go almost unnoticed. Kate is preparing her family to sail into royal life by giving them a normal life. And we should all recognise that as a huge achievement.”
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