Family and social networks are widely believed to influence important life decisions but identifying their causal effects is notoriously difficult. Using admissions thresholds that directly affect older but not younger siblings' college options, we present evidence from the United States, Chile,...

We study within-family spillovers in college enrollment to show college-going behavior is transmissible between peers. Because siblings' test scores are weakly correlated, we exploit college-specific admissions thresholds that directly affect older but not younger siblings' college options....