Meghan Markle and Prince Harry
Royal author Ingrid Seward claimed Prince Harry, seen here with Meghan Markle, Kate Middleton, and Prince William, was a "little in love" with his sister-in-law. Photo: Chris Jackson - WPA Pool/Getty Images/Getty Images Chris Jackson - WPA Pool/Getty Images/Getty Images

A royal author has made a bold claim that Prince Harry harboured feelings for his sister-in-law, Kate Middleton, which made Meghan Markle extremely jealous.

Royal biographer Ingrid Seward was asked about the possibility of reconciliation between the Duke and Duchess of Sussex and the Prince and Princess of Wales in an interview with The Telegraph about her new book, "My Mother and I".

"You can never say never but it's not that easy because they are miles apart," she said.

She also does not think that Prince William can ever forgive his brother for painting his wife in a bad light in "Spare". In his memoir, the Duke of Sussex wrote that Kate Middleton made Meghan Markle cry over an ill-fitting bridesmaid's dress for Princess Charlotte. He shared that his sister-in-law was being difficult about the whole thing.

Seward said that unfortunately, the problem "points to Meghan" and suggested that "Harry was a little in love with Kate". But she clarified that she does not mean romantically or physically but that he adored her mentally.

She explained: "No, no, no – I don't mean physically but mentally. Remember when it was just the three of them? He always longed for a sister, he told Diana that.

"Psychologically I think he just adored her and he was always there, at Kensington Palace, in their fridge, you know, 'What's for supper?'"

Seward's claims were met with raised eyebrows and laughter over at X, with one writing: "More ridiculous stories. It's Kate who's always been jealous of and intimidated by Harry's girlfriends. He's always said he sees her as a sister. Meghan's confident in, and safe with Harry's love. He adores her."

Another commented: "ROYAL FICTION ALERT. 😂😂😂 I apologise but this made me chuckle...The Prince Harry and Meghan love story is undefeated. But the desperate and pathetic attempts by royal rota /corespondents to re-write it is hilarious."

A third chimed in: "Kate was in love with Harry and jealous of the beautiful and accomplished Meghan."

Meanwhile, others suggested that it could be the other way around, that Kate Middleton was the one who had feelings for Prince Harry. They shared old news reports claiming the princess was overly involved in the duke's personal life .

Regardless, it is unclear how Seward got her information and if they are accurate. But she has been reporting on the British Royal Family for over 40 years as the editor of Majesty magazine. She has also been invited to family events where both Prince Harry and Prince William are involved.

She has been to Kensington Palace for meetings with Princess Diana. Given that she has been inside the palace, Seward also commented on how the former "Suits" star must have been jealous of Kate Middleton because she did not get to live in a palace.

Speaking about their royal residences, the royal biographer said: "I think that Meghan must have been incredibly envious and then jealous of Kate. I heard Meghan actually thought she was going to be a princess and live in Windsor Castle.

"Instead, there's William and Kate with this beautiful house, while they are stuck in Nottingham Cottage which Harry used to call 'my hovel'".

Prince Harry and Meghan Markle lived in Nottingham Cottage after they wed. It was also Prince William and Kate Middleton's home for two years and where they lived when they had Prince George. The Sussexes eventually moved to Frogmore Cottage in Windsor. But they rarely lived in it because of their royal tours. Then Megxit happened and they have since vacated the property as ordered by King Charles III because they no longer live in the U.K.