They were the closest of brothers, with the loss of their mother only solidifying the fraternal bond between Prince William and Prince Harry as they grew up.
But, now, as married men with responsibilities, cracks appear to be showing in their relationship – and it could be their wives who are pulling them apart.
It emerged yesterday that Harry and his wife Meghan are to move out of Kensington Palace next month to set up home at Frogmore Cottage on the Windsor estate.
News of the move comes after reports that the princes, who both have homes at the Palace, may be ready to set up separate courts.
The developments could reignite speculation of a rift between the Royal siblings – but a close friend of the Cambridge last night suggested any unease was between their wives.