I used to think the notion of Prince Harry being James Hewitt's son was a crazy conspiracy theory, but now I'm not so sure.
He seems so aggrieved about nothing much in particular that one wonders if he is and knows he is (through no fault of his) a cuckoo in the nest, despite always having been apparently treated considerately as "one of the family", and his current woes and self-imposed distancing from the royals stem from his internal conflicts of "living a lie" or some such.