The standard assumption is that teen mothers are less likely to have healthy children than older mothers. But my late father-in-law, who knew a lot of teen mothers as a public high school teacher in Chicago, questioned that conventional wisdom. Sure, if a malnourished 16-year-old peasant girl who weighed 90 pounds and had just gone through puberty at 15 got pregnant, that didn't bode well for the baby. But in his experience, the girls who got pregnant at 16 tended to be robust 150-pounders who had gone through puberty at about 11. He hypothesized that, say, NBA power forwards would tend to have younger mothers than the average man.