Over the weekend, the Prince of Wales offered an "olive branch" to his brother, the Duke of Sussex, by inviting him on a walkaround to meet mourners outside Windsor.
Now it appears that they could be reunited for the funeral itself as the brothers are prepared to "put their differences aside".
They were separated by their cousin Peter Phillips at the Duke of Edinburgh's funeral last year.
And they have only been seen in public together once since then.
But William and Harry are "not in the same place" as they were when Prince Philip died and could be ready to brave their differences out of respect for Queen Elizabeth II.
William and Kate with Harry and Meghan on Saturday
POOL
Queen Elizabeth II's coffin
Andrew Milligan
The Sun reports an insider as saying: "We are certainly not in the same place as Philip's funeral when William and Harry didn't walk side by side.
"Things haven't changed but it is not as intense and they can co-exist.
"But the flower visit really doesn't change anything. It is the same situation as at Prince Philip's funeral when William and Harry put their differences aside and supported each other and their families in that moment."
It comes as Prince Andrew also looks set to play a key role.
The Duke of York is expected to join his family, amid reports it would be "out of the question" for him to be excluded.
Mourners have been told to be prepared to stand for many hours through the night, if they want to see Queen Elizabeth II lying-in-state.
Those wishing to pay their respects to the late monarch’s coffin in London’s Westminster Hall will be able to file solemnly past 24 hours a day from 5pm on Wednesday September 14 until 6.30am on the day of the funeral – Monday September 19.
But the Government has stressed that the queue will continuously move – with little chance to rest or sit down – and the very long line of those waiting is expected to stretch through central London.
Guidelines reveal how people should behave and what they should wear, saying they should remain silent inside the Palace of Westminster.
Mourners are urged to “dress appropriately for the occasion to pay your respects”, banning clothes “with political or offensive slogans”.