OK, slight delay, but 2019Son went to pitching coach today, and had evaluation (including using high-speed video to break down his delivery -- which was cool to see in super slo-mo). Hit 75.1, so here's what I have:
Mar. 2013 (age 12 yrs, 2 mo.): 62 mph
April 2014 (age 13 yrs, 3 mo.): 70 mph
June 2015 (age 14 yrs, 5 mo): 75.1 mph