Another Reason
It is possible that given the evident tension between the four, it would only add fire to the mix when Queen Elizabeth II chose Harry to be the Youth Ambassador to the Commonwealth. William was offended he wasn’t chosen. He had the power to block this decision but chose not to.

Another Reason
Confirmation
Many fans of the Royal family aren’t quick to believe that there is a real conflict going on, and instead, blame the media for making it seem like there’s a real issue. On the other hand, the four were asked in an interview once if they ever got into disagreements, and William boldly stated, “Oh yes.”

Confirmation