Experts say Prince William has lost hope with estranged brother Prince Harry.
In conversation with the Mirror, royal writer Ingrid Seward shared that the Duke of Cambridge has come to a point where he no longer thinks he can help the younger brother.
She told the Mirror: "Despite appearing to do so, the two boys never got along particularly well. They sat down together for TV interviews on their joint reasons but they never got along. were also not very good friends.
"Kate has come a long way in encouraging their relationship and although William has always been looking out for Harry, she feels there is nothing more she can do at the moment.
"He knows what's in store for him and he knows how hard it is but with Kate's help and the support of his father, the Prince of Wales, he remains positive and optimistic about his future."
Meanwhile, Prince William celebrated his 40th birthday with the Queen, Kate and the rest of the royal family at a summer bash.