Meghan Markle ‘must have been incredibly envious and then jealous of Kate Middleton’, a royal expert has claimed.

Editor of Majesty magazine Ingrid Stewart suggested to The Telegraph that the Duchess of Sussex, 42, was perhaps jealous of her husband Prince Harry’s close sibling-like relationship with Kate.

‘Unfortunately, it points to Meghan doesn’t it? Maybe Harry was a little in love with Kate,’ said the royal author, before adding: ‘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?”.

Elsewhere, Ingrid, whose new book My Mother and I centres on King Charles III’s relationship with the late Queen Elizabeth II, said the ‘jealous’ Duchess ‘thought she was going to be a princess and live in Windsor Castle.’

Instead, the mother-of-two and her husband Prince Harry, who are now based in California following Megxit, were at first ‘stuck in Nottingham Cottage which [the Duke] used to call “my hovel”‘, while ‘there’s William and Kate with this beautiful house’.

The royal author continued: ‘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”.’

While Ingrid doesn’t write off the chance of a reconciliation entirely, she does say that distance – both physically and metaphorically makes it seem somewhat unlikely.

In December, an insider told The Telegraph that Meghan ‘felt she had more of a right to speak’ than Kate at certain events because she was a ‘self-made woman’.

The Duchess was allegedly uneasy with the Prince and Princess of Wales being the superior royals in the palace hierarchy when she joined the Royal Family.

This was particularly the case during a Royal Foundation Forum in February 2018, a source said, where it was claimed the tension between the ‘Fab Four’ was ‘palpable’.

Meghan felt ‘she was a self-made woman whereas Kate hadn’t really had her own career’, an insider told the publication.

The source said: ‘She seemed to feel like she had more of a right to speak than her sister-in-law, who had married into the family as an unknown whereas Meghan regarded herself as a philanthropist who could teach the royals a thing or two about charity.

‘I think she found it difficult that the Royal Foundation was already a well oiled machine by the time she got there.’

However, Omid Scobie previously claimed that Kate failed to foster a ‘meaningful’ relationship with her sister-in-law Meghan in his first book Finding Freedom.

It was also reported that Meghan received a ‘lukewarm’ reception from ‘formal’ William and Kate when her relationship with Prince Harry turned serious.

As Harry wrote in his book Spare, when he first introduced Meghan to his brother, Kate had remained in the garden – which wasn’t the welcome they had hoped for.

It comes after the Daily Mail’s Richard Eden revealed that the Princess of Wales, who underwent ‘successful’ planned abdominal surgery more than three weeks ago, is on the mend.

In a clear sign of her improvement, she was able to join her husband, Prince William, and their three children as they set off for a half-term holiday on the Sandringham estate in Norfolk, where the King is also convalescing.

‘Catherine is recovering well,’ a friend said. ‘She was looking forward to a change of scene and will be able to take it easy in Norfolk while the children let off steam with William.’

The Princess, 42, was discharged 12 days ago from the London Clinic, where she had spent almost two weeks.

In the only Kensington Palace statement about her health, a spokesman said on January 17 that, ‘based on the current medical advice, she is unlikely to return to public duties until after Easter’.

The spokesman did not provide details about the nature of her surgery, but sources briefed that it was not for cancer.

Since leaving hospital, without being photographed, Catherine has been at Adelaide Cottage, the family’s four-bedroom home at Windsor Home Park.

Her children, Prince George, ten, Princess Charlotte, eight, and Prince Louis, five, all attend Lambrook school a 15-minute drive away in Berkshire. They broke up for a week’s half-term holiday on Friday.