Why Meghan and Kate were kept apart at Trooping the Colour celebration

Kate and Meghan were at opposite ends of the balcony during Trooping the Colour. Photo / Getty Images

Last week, the Duchess of Sussex attended the annual Trooping the Colour, her first appearance since taking maternity leave.

But royal fans were quick to note Markle's position among the wider royal family as they took to the Palace balcony. While she stood three rows back, making it difficult for the crowd to see her, sister-in-law Kate Middleton had a prime front row position for the annual Buckingham Palace flyover, reports The Sun.

One royal expert told People magazine last year that the standing arrangement for the royals on the balcony is determined by the line of succession.

The Duchess of Sussex made an appearance for Trooping the Colour hid at the back, far from the Duchess of Cambridge. Photo / Getty Images

Joe Little, managing editor for Majesty magazine, explained: "She (Meghan) was not as prominent perhaps as some people might have expected, but there's a pecking order.

"There was no slight intended, but William being the older, more senior brother would go out [first] with his wife."

However, according to People magazine, a royal sourced clarified that a set positioning does not exist and it would have been Markle's own decision to stand where she was.

The anonymous source explained: "(It) would have come from her. There's no one laying this out, telling her where to stand.

"And there were a lot of kids who everyone would want at the front."

The occasion held for the official birthday of the Queen finished with the royals observing the Royal Air Force flying above them.

While Kate had a prime spot, all eyes were on Prince Louis, who made his first balcony appearance at a royal engagement.

Royal baby fans who were hoping to see the Duke and Duchess of Sussex's son Archie were left disappointed.

A royal expert says how the royals stood on the balcony was arranged. Photo / Getty Images

Majesty magazine told The Sun that is one decision the Queen may have had a say in: "The Queen, through her private secretary, could easily have said Archie was far too young for the Palace balcony, which indeed he is.

"She herself took baby Prince Edward onto the balcony in June 1964 but he was three months old and she was the Queen so she could do as she liked!

"Her view would be that it is an event to be enjoyed by children, but no younger than Prince Louis as they must be able to behave properly.

Prince Louis of Cambridge put on a show for his debut royal engagement. Photo / Getty Images

"The last thing she wants is for millions of TV viewers to witness a childhood tantrum."

Markle's first appearance came soon after she snubbed Donald Trump's state visit.

The Duchess of Sussex won't be returning to work until Autumn but will join the Duchess of Cambridge for some outings, and is rumoured to be planning trips to South Africa, Angola and Malawi in the near future.