WATCH the vid below to hear royal commentators discuss all there is to know about the Prince Harry and Prince Wiliam feud!
But now a royal source reveals that it is actually Harry and Will who are feuding, and the tension dates back to a continuous set of incidences that left Harry feeling upset and left-out.
According to royal biographer Katie Nicholl, the Queen Mother would often favour Prince William over Prince Harry.
Nicholl claims that the Queen Mother's favouritism made the young prince “acutely aware of his position” as third-in-line to the throne behind his brother, Prince William.
Nicholl also claims that the royal red-head was “particularly upset” when the Queen Mother showered more attention on his older brother.
Nicholl writes in her 2017 book Harry: Life, Loss and Love that Princess Diana's close friend Simone Simmons recalls young Harry's hurt feelings.
Ms Simmons said: “I remember Harry complaining that when he and William were with the Queen Mother, that William was always the centre of attention.
“William would be sitting next to the Queen Mother in a drawing room that dwarfed the pair of them, and Harry would be sitting at a distance from them keeping himself entertained.
“He was particularly upset when, on one occasion, the butler brought sandwiches just for her and William.”
According to Express.co.uk Ms Nicholl has written that it's not just the Queen Mother who showed special interest in William and not Harry, but claims that as the two got older the Queen herself would seek a weekly meeting with William and not Harry.
Of these weekly meetings, Ms Nicholl wrote:“[The Queen] considered it vital preparation for his future role as king.”