The line of succession goes from the Prince of Wales (Charles) to his son Prince William, the Duke of Cambridge to his son Prince George of Cambridge. Prince Andrew drops a notch every time that one of Prince Charles’ son fathers a child.
But could it go Elizabeth to Wills, or Elizabeth to Andrew?
"The British Constitution requires that succession passes to the oldest heir, male before female, of the reigning monarch. If there is no direct heir, the line passes through brothers or sisters of the Monarch, but excludes anyone who is Catholic or married to a Catholic."
In any case, it's really not worth wasting time pondering as Elizabeth would never renounce Charles and Charles will outlive Elizabeth.
It would be great if he abdicated to Wills shortly after being crowned though. The Brits may tolerate Wills and Kate and baby George... but how long will they be interested in supporting the crown while it rests on the heads of Charles and Camilla? Heh!
The real question is, will Charles stubbornly hold on to the throne even if he knows he is unpopular and it threatens the future of the monarchy? He just might! What do you think?
UK just last year passed a law making succession by absolute primogeniture rather than male preference primogeniture.
IOW, whether a person is male or female will no longer play a role in succession.