Thanks, everyone!
I also have a son slightly older. I just know in advance he will not be so cool about it, so I am telling him later, after I tell my wife.
Full disclosure with my wife is coming soon. How soon I do not know, but since I promised myself I will not start taking my Estradiol and Spironolactone until I have had this discussion with my wife, and given the fact that I really want to start my HRT as soon as possible, I will have to tell her soon. Then I will tell my son.