He's a DJ - albiet a polo playing DJ friend of the Wales boys. The sister who married Branson was a wannabe actress and of course the mom had that infamous motor oil photo and the cousin is an actor as well. The only loose lips in the Middleton clan are Uncle Gary and 12th cousins who've never met Catherine, the Bonas/Strougth/Calthorpe etc. clan looks to be more fertile ground for leaks and the like.
What is fascinating is that the brother said a few rather innocuous things, to wit, Cressida is sweet, Cressida wouldn't do anything to embarras Prince Harry, it must be hard to date a royal and go through what Catherine did and he doesn't relish the thought of being subjected to all the scrutiny the Middletons have been [can't blame him for that - probably more than a few skeletons in his extended family closet] his family is very private, it is exhausting to deal w/ all of that media attention.
Significantly he said nothing about the state of his sister's relationship and nothing about her thoughts or feelings about her future - nothing, nada. Yet the headlines for the stories running these quotes are:
Hello: ...Brother addresses rumors of another royal wedding
Telegraph: Cressida may struggle as a Princess, brother warns
Mirror: Brother...[says]Cressida...has fears over her royal romance
I've known for years that the press (including the so called serious press) never let the facts get in the way of a good story and were incapable of correctly quoting you or loved to pluck things out of context to make it seem you'd said the opposite of what you actually said - so no surprise at these ridiculous headlines based on a few off the cuff remarks by the half brother.
And we wonder why most Royals are so careful and guarded in their speeches - I offer the above headlines as exhibit A.