An over-enthusiastic fan from across the pond caused a stir as she grabbed Kate Middleton's hair as the Princess of Wales and Prince William met royal fans ahead of tonight's Coronation concert at Windsor.
The future Queen appeared to be taking the incident in her stride as she leaned in and smiled for a selfie with the overexcited fan from the United States.
Images and video footage show the woman grabbing Kate's hair after asking for a photo with her.
A concerned security guard quickly steps in to push the fan's hand away from the Duchess, while another security guard approaches to assess the situation.
Despite the security scare, Kate remains calm and collected, flashing a friendly smile for the selfie.
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After the photo is taken, Kate politely tells the fan "nice to meet you," indicating that she was not overly alarmed by the incident.
The fan, who is clearly thrilled by the opportunity to meet the Princess, squeals with delight before apologising to the security guard who pushed her hand away.
In another video filmed during the walkabout, Kate hugged a crying little girl in a touching moment.
The Princess gave the teary youngster, who was wearing a headband with union flag deely boppers and a navy dress covered in patriotic motifs, a long hug and the girl started crying.
As Kate had crouched down to speak to her, she continued chatting with the girl, who nodded her head and gave a small shrug as Kate patted her back.
The little girl wore a red fluffy hairband with Union Jack flags sticking out on either side, as well as a dark blue dress emblazoned with crowns, Union Jacks and London buses.
A family member filmed the special moment at a walkabout for the Big Lunch in Windsor on Sunday.
Kate also comforted another little girl, named Lucy, who got emotional when she met the Princess.
William and Kate made the unannounced appearance ahead of Sunday’s star-studded coronation concert at Windsor Castle and were seen shaking hands and chatting with revellers.
Royal super fans crowded around the couple, with William crouching down to chat with a boy and girl wearing golden crowns.
The couple looked relaxed, with William telling one group of well-wishers: “Enjoy the concert tonight”.
Lionel Richie, Katy Perry and Take That will headline the show, along with the likes of X Factor star Olly Murs and pop sensation Paloma Faith.
The concert, hosted by Downton Abbey actor Hugh Bonneville, will see Hollywood star Tom Cruise, Dynasty actress Dame Joan Collins, adventurer Bear Grylls and singer Sir Tom Jones appear by video message.
The series of pre-recorded sketches will reveal little-known facts about the monarch and will also include moments from beloved literary figure Winnie the Pooh – seemingly echoing the famous moment Paddington Bear drank tea with the Queen during her Platinum Jubilee celebrations.