All smiles... Kate, Duchess of Cambridge, left, and Meghan Duchess of Sussex, right, arrive to attend the Christmas Day service at St Mary Magdalene Church in Sandringham. Photo / Getty Images
The British royal family knew their every move on Christmas Day would be closely watched and talked about - so the Queen didn't leave anything to chance.
Her Majesty reportedly wanted royal wives Kate Middleton and Meghan Markle to put their differences aside and put on a happy, united front as they walked in the cold air of Sandringham for their annual church service.
Hundreds turned out to get a glimpse of the royal family, but it was Kate and Meghan who most eyes were firmly fixed on - and in particular for any sign of the supposed feud that has erupted between the pair.
Britain's mass-selling The Sun reported exclusive details of the truce The Queen and Prince Charles reportedly ordered the pair to make.
Both had made it clear the rift must be kept out of public during the royals' traditional Christmas gathering.
A source told The Sun: "The Queen and Charles have allowed the situation to play out without overtly interfering — but they both made it clear that Christmas was for the whole family to really come together.
"That meant the two couples walking into church together as the Fab Four just like they had last year. Yes, it was awkward and uncomfortable given what's gone on over the past 12 months."
It was felt that was better than the alternative situation, which was "even more negativity on Christmas Day".
It's believed the Queen also wanted the pair to be on friendly terms by the time her Christmas message was played on television at 3pm (local time).
During that message she spoke about the busy year her family had had, with weddings and babies - and Meghan and Kate featuring prominently during her "well occupied" year.
She also spoke of the need for people to put their differences aside , in what many consider was a pointed message aimed at British politicians and their Brexit disagreements.
"I believe this message of peace on Earth and goodwill to all is never out of date. It can be heeded by everyone; it's needed as much as ever," she said.
Meghan, 37, and Kate, 36, have been the subject of relentless speculation that they do not get along. Unnamed royal sources have claimed they have argued - over Meghan's treatment of staff, and indifference to royal protocol - but the palace has only denied they fought over words Meghan apparently had with Kate and William's staff.
In keeping with royal policy, the palace has not confirmed or denied anything else. Experienced royal watchers have noted the two women have very different backgrounds and it would be no surprise they aren't best friends which would obviously jar with the public who would like them and their husbands to be close.
Meghan has also been accused of driving a wedge between Princes Harry and William, and of making Kate cry after a tense bridesmaids dress fitting for Princess Charlotte ahead of Meghan's wedding in May.
Veteran royal watcher Phil Dampier, author of Royally Suited: Harry And Meghan In Their Own Words, told news.com.au last week he expected there would be happy scenes in public.
"I'm sure the fab four will be all smiles as they walk to church and put on a show of unity, but royal watchers will be studying the body language."
But where Meghan and Harry actually spend that night will provide the biggest clue as to what is really going on.
The couple spent last year with William and Kate, but have reportedly turned down an offer to stay with them again this year at their home Anmer Hall, on the Queen's Sandringham Estate.
Dampier said that would give the biggest hint.
"The key is whether Harry and Meghan stay at Anmer Hall or the big house. If it's the latter, I think we can assume there is still a problem."
Meghan and Harry didn't spend the night at William and Kate's and body language experts have had a field day with studying them.
One expert, Judi James, told The Sun it appeared as though Kate was making the most effort to be friendly.
"Meghan clung to Harry's arm at first. But instead of sticking beside William, Kate deliberately stepped away to walk close to her sister-in-law."
James added: "Kate was also clearly making a supreme effort to smile and chat to Meghan.
Yesterday was the first time Meghan and Kate had been seen together in months. They were seen chatting happily and smiling at each other, as they walked side-by-side to the church.
At one point Meghan put her hand on her sister-in-law's back to guide her along the path.
The brothers also appeared to be getting along fine as they walked alongside their wives.