India, Sept. 23 -- British author and journalist Charles Spencer, the younger brother of the late Princess Diana, has reopened old wounds within the British royal family with his new book, Swan Song: Diana, My Sister, which went on sale on Tuesday. The book revisits Diana's life, her unhappy marriage to then-Prince Charles and the events surrounding her death in 1997. In excerpts and in interviews with multiple news outlets, Spencer claims Charles was "giddily elated" after Diana's death and alleges that the now-King told him, "We'll forget her soon enough". He further recalls Charles objecting when Spencer questioned whether Diana's sons, William and Harry, then 15 and 12, should walk behind their mother's coffin at her funeral. Buckingham Palace has strongly challenged Spencer's account, saying, "The pain of fraternal grief can cloud reason, affect judgment and colour memory." Spencer, who describes himself as an "eyewitness to history", called the response "astonishingly provocative and below the belt". HTC...