Dorante-Day shared a side-by-side image of himself and Prince William sporting a similar smile, leaving viewers “stunned” by the similarities.
Royal watchers said the couple were ‘brothers from another mother’, with one adding ‘there is no doubt’ Prince William was Dorante-Day’s younger brother.
A third said, “Wow, Simon. It’s just a younger version of you. “
Another wrote: “Well now we know what he will look like in a few years! “
“The resemblance in this photo of you and William is just crazy,” said a fifth.
A Facebook user – who described herself as a staunch skeptic – called the caparison “undeniable.”
“Truth be told, I hadn’t really seen it before – but undeniable in these comparison photos,” she said.
The Australian father also shared a photo collage comparing his daughter to Princess Charlotte and the Queen as a young girl.
A few weeks earlier, he had posted a photo comparing his son to the Queen.
Durante-Day made headlines earlier this year when he claimed to be the secret child of Prince Charles and Camilla.
DO NOT BACKWARD
The Royal-wannabe, who was born in the UK but now lives in Queensland, Australia, claimed he was conceived in 1965 when he said Charles and Camilla were first romantically linked .
The 55-year-old father-of-nine believes the couple conceived him when Charles was just 17 and Camilla 18 and he was later adopted by a family with royal ties.
Since going public with his wacky claim, he has shared numerous side-by-side images comparing himself with his son to the Royals, including one with Charles, Camilla, the Queen and Prince Philip.
Speaking to 7NEWS.com.au, Simon said: “All the royal fans and supporters who send them to me, they are amazing.
“And I really think it’s like an Agatha Christie novel to them, where they’re looking for clues and answers.
“There are so many people invested in my story now and helping me, it’s really amazing. “
In June, he scandalously said his teeth had been ground flat by a dentist to make him look less regal.
He claims he was ‘pinned down’ by a dentist for shaving off his sharp canines and erasing any similarities to the royal family.
Sharing a photo of the Queen, Durante-Day wrote: “This photo illustrates why my canines were ground flat. “
Durante-Day was born in Gosport, Hamps, in April 1966.
He has filed documents with the High Court in an attempt to force the Duke and Duchess of Cornwall to undergo a DNA test.
The engineer claims his adoptive grandparents Winifred and Ernest worked as a cook and gardener for the Queen and Prince Philip and told him “on several occasions” that he was Charles and Camilla’s child.
He also believes that the names of his birth parents are “fictitious” and that the official documents of his adoption are handwritten by his mother.
Unsurprisingly, Charles and Camilla did not respond to his claims.
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