  More children in Shandong Province are stunted than any other province in
China. Data on more than 122,000 children show a dramatic increase in height
advantage with birth order in Shandong relative to the average of other
provinces. We suggest that the steep birth order gradient in Shandong is due to
a preference for the eldest child, which influences parental fertility
decisions and resource allocation to children. We show that within Shandong
province, the gradient is steeper for regions and cultures with a high
preference for the eldest child. As predicted, this gradient also varies with
the sex of the sibling. By back-calculating, the steeper birth order gradient
in Shandong Province explains more than half of the average height gap between
Shandong Province and the rest of China.
