The rift between Prince William, future king, and Prince Harry, now sixth in line to the throne, shows no signs of mending. Neither have opened up publicly about the underlying causes, but now royal biographer Andrew Morton author of Diana, Her True Story, and Meghan: A Hollywood Princess, has suggested one possible aggravating factor.
According to Morton, William was baffled by Harry and Meghan's refusal to name the godparents who would be appointed to guide their son, Archie, now two.
The private christening took place on 6 July 2019 in a private ceremony held at St George's Chapel in the grounds of Windsor Castle, and the couple maintained a wall of silence over who their chosen godparents would be.
Godparents are usually close friends or family of the parents, entrusted to support and help raise the child, and in the Christian tradition, to help mentor the child spiritually.
Watch: Prince George stole everyone's heart at Prince Louis' christening
The Royal Family worships within the Church of England, where traditionally, girls usually have two godmothers and one godfather, while boys have two godfathers and one godmother.
When Archie was christened by the Archbishop of Canterbury, however, no names were initially forthcoming.
While for many modern families the idea of godparents may be outdated, for the royals it's still a very big deal – godparents are trusted confidantes who can be relied upon to remain loyal, never to embarrass the Firm, and who will definitely still be around as the royal baby grows up.
William and Kate chose several godparents for Prince George, making the names immediately public on royal channels as was usual.
They included Oliver Baker, who went to university with the couple; Emilia Jardine-Paterson a school friend of Kate's; Hugh Grosvenor, son of the Duke of Westminster; Jamie Lowther-Pinkerton, their private secretary; Julia Samuel, a close friend of Princess Diana's; William and Harry's cousin Zara Tindall, and William van Cutsem, William's oldest friend.
According to Morton, Harry and Meghan's decision to keep the names private was "another issue" that "perplexed William".
"He, like others in the family, felt that those chosen to guide and counsel a future royal prince, seventh in line to the throne, should be identified,"
The couple 'thought otherwise' however, he said, as " the godparents were genuine friends, not celebrities or public figures, and had joined with the royal couple in preferring privacy".
Several days after the christening, the puzzling silence had become such a hot topic of debate, the names were finally revealed.
The godparents were Prince Harry's childhood nanny Tiggy Pettifer, (formerly Tiggy Legge-Bourke, who reportedly fell out his his mother, Princess Diana), his old friend Charlie van Straubenzee, and Mark Dyer, Prince Charles' former assistant.
The 25 guests included William and Kate; Charles and Camilla; Meghan's mother Doria Ragland; and Diana's sisters, Lady Jane Fellowes and Lady Sarah McCorquodale.
The Queen had a prior engagement, and did not attend.
Now, the christening of Archie's sister, baby Lilibet, born in June, will be imminent - but as yet, Harry and Meghan have not clarified whether she will also be christened at Windsor, in a move to reunite the warring family, or in Santa Barbara, which is now their home.
It seems the row won't be healing at the moment, however. Despite Harry's well-publicised visit in July to unveil a statue of Diana alongside William, the brothers remain frosty.
After the Oprah interview in March, William broke protocol to snap, "we are not a racist family" to reporters, in the wake of Harry and Meghan's allegations that a senior royal had 'questioned' the colour of Archie's skin.
Despite a cool exchange of birthday wishes on their official Instagram accounts since, it seems that very little has changed between the brothers, or their wives.
In the infamous Oprah interview, Meghan spoke about the 'row' with Kate over the bridesmaids tights, insisting that she had cried and sent flowers. Royal insiders, however, have claimed that it was Kate who was upset.
Although recent speculation suggested that the Sussexes may head to the UK for Lilibet's christening, the baby has not been seen in public in the months since her birth, and it seems the couples' desire to control their public image and appearances is stronger than ever.
According to NBC's royals correspondent Neil Sean, quoted in the Express, it was William who blocked the British christening plan.
“Both Harry and Meghan were very keen to make that return and make sure that christening happened, particularly in front of Her Majesty The Queen,” Sean said, “But that came to a grinding halt.
"There was one person who basically decided there wasn't an appetite for this and the person that seemingly is, so far, not willing to kiss and make up with his younger brother...
"According to a very good source, Prince William was the one who basically said 'no, we don't think this is going to work,' it wasn't a particularly good idea."
The royal rift rumbles on and as for who will be Lilibet's godparents, it's a good bet that right now, it won't be William and Kate.
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