King Charles III was pictured smiling and waving at his fans on Sunday morning, as he made his way to St Mary Magdalene Church in Sandringham for a service.
The 76-year-old was all smiles as he greeted people warmly from the backseat of a blue car, but royal fans noticed that there was a peculiar absence.
Though he is usually joined by his wife, Queen Camilla, when he goes to church, she appeared to have missed out this time.
The beaming British royal was dressed smartly for the service, in a dark grey suit with a crisp white shirt and a tie.
As their Majesties have been taking a break from their public duties since they returned from Canada, it is possible that the Queen simply needed to take some rest, especially ahead of their busy summer calendar, which includes Trooping the Colour to mark the King's official birthday, Royal Ascot, and an incoming state visit from President Macron in July.
King Charles and Queen Camilla's state visit to Canada
During the couple's two-day visit to Ottawa earlier this week, their Majesties carried out a series of back-to-back engagements, which culminated in the King delivering a 26-minute speech during the state opening of Parliament.
Charles and Camilla were met with a warm reception in Canada, and took their time to shake as many hands and greet as many people as possible during an event in Lansdowne Park and while they walked to the war memorial after the state opening.
According to a senior royal aide, the King was "touched" by the response from Canadians, adding: "To go to a realm of which you are King, but in which you don't actually live is a big thing when you do it for the first time, as we saw in both Australia and now Canada."
They continued: "It is a reset of that relationship, and for Their Majesties to see so many people turn out and to be so thrilled to see them was fantastic.
"As The King put it in his departure message that came straight from the heart: 'It was the warmest of welcomes and the fondest of returns to a nation and a people we love'."
King Charles is living life as 'normal as possible'
The senior royal aide also noted that the King is "managing" his cancer and trying to live life as normally as he can with his ongoing treatment, as neither the Queen nor his advisors have been able to convince him to take a breather.
They said: "The thing you learn about this illness [cancer] is that you just manage it. And that's what he does. Medical science has made incredible advances and I genuinely see no difference in him.
"As long as you just do what the doctors say, just live your life as normal as possible and that's exactly what he is doing."