After being the "patient" with an older neighbor boy, I became the "doctor" with my younger brother. We would have marathon Monopoly games, and the winner would get the opportunity to do whatever he wanted to the loser. My brother lost many games so I had the chance to practice my examination, spanking and fondling techniques quite extensively on him.
Because he was shy we would begin with him laying face down on his bed, naked except for his white brief underpants. With my left hand squeezing a butt cheek to hold him down, I would snake my right hand up under from behind in search of his hidden naughty boy bits. As I found and began fondling his penis and scrotum through his briefs, he began to moan and writhe about---too much movement and a sharp hand spanking would commence.
After the spanking settled him down, he was ordered to turn over and lay on his back so I had complete uninhibited access. Following brief inspection of his still covered front, I slowly pulled down his underpants, removed them, then pushed his legs wide apart to continue my examination and palpation in methodical detail. His genitals were small and undeveloped at that time, but his little cut penis would get hard, and he had a couple beginning stray blond pubic hairs here and there around the smooth soft ballsac which contained his young firm testicles...very cute and fun to squeeze, stretch, tickle and intimately explore from pleasure to discomfort.