If the son is not transgender,

Possibly TMI:

I don't consider myself transgender, but I have been wishing this had been done to me pretty much since I was 12.

The main thing I learned from this article is that everything I thought I knew about castration holds up under Lesswrongian analysis, including the part where I completely missed the opportunity and would probably be more likely to die early were I castrated now. There would still be some advantages, but it seems too late to be worth it.

You did specify "presumably normal", though. Presumably, I am far from normal.