As a bit of an aside, I was thinking about this of the latest royal conception (I know, I know, but bear with me.) We often say that XYZ is nth in line to the throne. When child is a year old that same person is (n+1)th in line. So when does it change? When the pregnancy is announced? When the birth takes place? So is Harry currently 5th or 6th in line?

I don't care a jot, actually, apart from that it a quirk of the system...