Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
It is notoriously difficult to identify peer effects within the family. Using administrative data on children from both Florida and Denmark, the paper examines the effects of having a disabled younger sibling. To address the identification challenge, the paper compares the differential effects for first- and second-born children in three-plus-child families, taking advantage of the fact that birth order influences the amount of time that a child spends in early childhood with their younger siblings, disabled or not. The paper finds evidence that, relative to the first born, the second child in a family is differentially affected when the third child is disabled.