A Princess of Wales lookalike has hit out at “crazy” speculation that she is in the footage with Prince William at Windsor Farm Shop instead of Kate.

Heidi Agan, who has impersonated the royal professionally for 12 years, stressed she “100 per cent” believes Kate and William are in the footage – because she, at the time, was doing her “other job” – as a teacher at a dance and musical theatre group.

Heidi told the Mirror how her social media went into meltdown at the suggestion she had been wrongly mistaken for the real Kate, 42, when the future queen was snapped at Windsor Farm Shop on Saturday. It comes as the Princess of Wales continues to recover from abdominal surgery, which she underwent in January and hasn’t made any official public appearances since Christmas.

Speaking to the Mirror, mum-of-two Heidi said: “There has obviously been some speculation about whether it was Kate and William in that footage and stills. In fact, my own social media has gone crazy as people think it is me, but I know it is not. I was at work at the time so I know that is not me. I 100 per cent believe that is Kate Middleton and William in that video.

“So she is alive, and we can be sure about it. It has all gone too far now. It started as a joke about where is Kate’ but now it has turned into a drama really, so it needs to stop.”

Some on social media questioned the authenticity of the video after weeks of wild conspiracy theories spread online. But Nelson Silva, who took the video, insisted today it was real.

Heidi, 43, has impersonated Kate professionally at parties, meets and greets, corporate events and other gigs since 2012 when working as a waitress, customers regularly pointed out she looked like the future queen. Heidi shrugged off the suggestions for six months until she gave in, and offered her services as a Kate impersonator. The work rolled in and Heidi was able to quit her day job within weeks.

She says the last few months have been difficult as speculation about Kate’s health has grown. However, the mum now feels the public need to cut Kate and her family some slack and give her the time to recover from her procedure.

Speaking from her home in Northamptonshire, Heidi continued: “If the surgery is something that she wanted to keep private, then they [Kensington Palace] are right not to share more details. She is a public figure but not public property, and we must respect that.

Heidi teams up with a colleague who plays William at the gigs ( Image: katemiddletonlookalike /Instagram)

“My social media has gone crazy since the video emerged. It wasn’t me. Joking about Kate is one thing but we need to give her time now and I’m sure she’ll be back after Easter, like what was said in the first place.

“Since Kate has surgery, I have done gigs where I have walked in and people have said ‘there’s Kate” so it started as a joke around ‘we’ve found Kate’ but now it should stop really.”

Heidi now performs alongside colleagues who impersonate Prince William, Prince George, Princess Charlotte and Prince Louis, and even lookalikes of the family’s dogs and hamster. The group perform everywhere across the world, from London to Hong Kong.

“There is a worldwide fascination about the British Royal Family. It is the closest you’ll get to the real Royal Family, I suppose. I have always followed them myself but didn’t believe I looked like Kate,” Heidi, the former waitress, said.

The mum, who is originally from Cheslyn Hay, Staffordshire, posted on Instagram an image taken at her other role on Saturday – when Kate was at Windsor Farm Shop. However, some of her 3,000 followers had previously been convinced she was the woman alongside her “William colleague” in the footage.

The doppelganger has changed her appearance to reflect Kates over the years, including during her pregnancies (Image: katemiddletonlookalike /Instagram)

One Instagram user said: “I think the woman in that picture is you.” Another shared: “It was this lady at the farm shop.” A further user had posted: “How much did you get paid for pretending to be her at the farmers market?”

But, sharing her alibi with The Mirror, Heidi continued: “The Royal Family are just quintessentially British and I think that’s why everyone follows them. They are our constant and we are interested in them, whether we love or loathe them. I myself like them. My work is just supposed to be a bit of humour, and it’s often a surprise to the audience so it’s fun.

Heidi and her colleague have also, at times, teamed up with Meghan and Harry lookalikes ( Image: katemiddletonlookalike /Instagram)

“It is always a big surprise to my clients. I appear and then there’s general chit-chat. I have lived in several places so have a mish-mash of accents, and have had to look closely at how Kate talks and behaves. I am always mindful of how she talks. I think all lookalikes study their subjects closely because you have to, you have self-teach… There are mannerisms. Kate, I’ve noticed for instance, sometimes bites her lip – I’m not sure if that’s when she’s nervous or what.