A few years ago, I read the account of a famous lady astrologer ( do not recall her name) who looked at Prince Charles' chart, Prince William's and Prince Henry's charts.
Her findings was that neither Charles nor William would be king. Charles, we know, now lives on borrowed time. He is a king in name only as he "recuperates". The astrologer never mentioned what happened to William, only that there would be a regent appointed for the crown. In terms of next in line, Henry is the obvious choice after his three little nephews/niece.