One of my grandfathers, actually, having gone out there as a minister, decided he would better serve the people as a doctor. So at a very late age - at the age of 38 in fact - he changed course and decided to become a doctor. ↗
I've never taken vocal lessons. My early trumpet training and a fortunate talent for singing has always been enough for me. In the case of rock singing, I've always felt it was better to remain a bit untrained to maintain your individuality. ↗