My DH was 5'10" when he graduated high school, wore a size M shirt, no facial hair at all, and voice still hadn't dropped. (sounded like Mickey Mouse with a Southern accent on helium, lol).
We started dating when he was just barely 22. He was 6', wearing a size L-XL shirt. Shaved his face once a month, even though it was all peach fuzz, and forced his voice down an octave when he talked.
Together for almost 27 years. He's now 6'4", 3XLT shirts, a beard down to the middle of his chest, and his voice is deeper.
I used to give him grief that our DD (born when he was 23) would hit puberty before him.
That is super strange. Maybe he should have been studied. That is not at all common. One of my cousins was like that at the end of HS. He was found to have a pretty major hormone issue that needed treatment. If he hadn't done it, he would have ended up infertile.