This prediction is a "best guess" but it's still just that -- a guess. Based on the formula we used* there is a 50 percent chance that your girl's full-grown height will be within 0.7 inches (above or below) of this prediction, and a 90 percent chance that it will be within 1.7 inches.
THE FINE PRINT: Parents' heights are a good predictor of a child's adult height, but heredity only accounts for about 70 percent of what goes into deciding how tall someone will be. The other 30 percent comes from environmental factors, like eating habits (poor nutrition can "stunt" a child's growth) and exercise patterns (a competitive gymnast may not grow to her full potential).
