RICHARD KAY: As yet more squalid details emerge about Thomas Markle’s private life, it is hard not to feel sympathy for Meghan… and that’s also the sentiment at the Palace

A week ago, there was incredulity amid the shock, as cautious voices urged no rush to judgment. Today’s revelations by the Daily Mail of a second stash of child pornography allegedly linked to the Duchess of Sussex’s estranged father require a different response.

The discovery of books and magazines about paedophilia and photographs – some of young children on a beach – which the Mail has reported to the FBI, will be another devastating blow to Meghan.

One unsettling photo shows Thomas Markle Sr sitting on a hotel bed with his arm Around a young Asian girl. Both are clothed but other images feature the same girl alone, naked and lying in sexual positions.

What is especially troubling about this latest discovery is that the hoard was not recovered from Markle’s temporary home in the Philippines – in interviews with The Mail On Sunday last week, he admitted being a sex tourist in South-East Asia – but at a storage unit close to the apartment in a Mexican border town where he was living an apparently blameless life at the time when Meghan had first met Prince Harry.

There is also one other important difference. It was Markle’s son, Thomas Jr – Meghan’s half-brother – who unearthed the boxes of material in Cebu, the Filipino city where he had been living with his father.

His involvement prompted an unpleasant war of words with his other sister Samantha, who accused him of inventing the ‘disgusting’ allegations to make money.

However, the sensational discovery in Rosarito, Mexico, had no Markle family involvement and no claims of tawdry domestic score-settling. It was made by Daily Mail reporters who independently confirmed from invoice receipts that the 5ft-by-10ft lock-up containing the material had been rented by Markle when he moved to the town ten miles south of the US border in 2011.

So, what impact will this deeply troubling new development have on the duchess, and indeed on the wider Royal Family?

What seems clear is that it is no longer possible to dismiss the original revelations as simply part of some sordid dispute between the feuding Markles.

Thomas Sr, who is undergoing rehabilitation in Florida after having part of his leg amputated and a prosthetic limb fitted, has denied any wrongdoing.

His home in Rosarito played a key part in the Harry and Meghan story. It was where Markle, an award-winning former Hollywood lighting director, lived a reclusive life in a gated community.

And it was where he found himself dragged into the global fascination with the relationship between his daughter and the late Queen Elizabeth’s grandson. He famously – and foolishly – collaborated with a photographer to manufacture pictures of himself preparing for the royal wedding. Humiliated when it was exposed as a stunt, he then declined to attend the wedding, having suffered a heart attack.

The relationship with his daughter never recovered.

But as, little by little, more unsavoury details about Markle’s private life emerge, it is hard not to feel sympathy for Meghan and to understand why she has sought to put so much distance between herself and the Markle clan.

In retrospect, how relieved she must be that there are no wedding photographs of her and the Royal Family smiling with the man now engulfed in such seedy and squalid allegations.

Had he led his daughter up the aisle of St George’s Chapel in 2018, Thomas Markle would have been in all the official pictures, almost certainly sitting on the front row with his daughter, the then Prince Charles, the Queen and Prince Philip. How toxic such images might look today.

Might this even explain some of her curious decisions to protect her children’s privacy by, for example, not posing with Prince Archie when he was born in 2019?

We now know that four months before her son’s birth, Meghan was shown a letter – written by her father’s first wife, Roslyn Loveless – in which she is said to have warned a specialist police unit that assesses threats to royals and public figures about Markle’s apparent proclivities.

This letter is thought to have been shared with other senior officers close to the Royal Family, before it was subsequently ‘lost’ by the authorities. Now, of course, it is at the centre of another row involving Scotland Yard, which has reported itself to the police watchdog for its alleged failure to alert other law enforcement agencies about the message’s contents.

It is impossible to avoid the conclusion that, had the Yard done its job at the time, Mexican and US authorities might have investigated Markle seven years ago. Instead, it has fallen to the Daily Mail to uncover his sleazy secrets. Imagine Meghan’s distress at receiving such news while preparing to become a mother for the first time.

With the benefit of hindsight, that disclosure is significant. She had always described herself as a ‘daddy’s girl’: that letter must have brought her world crashing down.

In this light, one exchange on the Oprah Winfrey sofa during that notorious 2021 interview may need to be reconsidered. Speaking about her estrangement from Markle, she observed: ‘I grieve a lot. I mean, I’ve lost my father.’

Now viewed in the light of the Mail’s shocking discovery, Meghan’s shielding of her children – including the refusal to issue newborn pictures and to continue to obscure their faces even as she posts pictures of them online – takes on a different and more nuanced complexion.

Can we honestly say that private christenings, the obscured photographs and their absence from royal pageantry were necessarily proof that she was, as some critics insisted, ‘Duchess Difficult’? Instead, perhaps we now see a mother determined to build a wall around her family, protecting her young children from dark, sinister secrets despite relentless pressure.

Meghan, it seems to me, placed family before royal duty. Given what we now know, who really could fault her?

For the King, this latest salvo of disclosures will also call for some recalibrating. There will certainly be no blame from Buckingham Palace that the allegations have overshadowed his important tour of the Caribbean. They are not Meghan’s fault.

He will naturally feel a Christian duty to offer her and Harry his support. Whether that translates into reconciliation and reintegration with the rest of the Royal Family, and in particular the Prince and Princess of Wales, remains to be seen.

‘There will be considerable sympathy for Meghan but that alone will not eradicate how family members feel she and Harry have behaved,’ says a close figure.

The other question, of course, is whether public attitudes will soften, too.

For now, all eyes will be on the contents of the 20 boxes found in Markle’s storage unit. They, as much as anything, could determine not just matters of innocence or guilt in faraway Mexico but also the reframing of the Royal Family.