Abstract
Sympathy is regarded as an important precursor to the development of emotional intimacy, including mutual disclosure. In turn, emotional intimacy is assumed to foster the development of sympathy. Yet, research has not examined how sympathy and mutual disclosure in generic friendships are mutually related to one another during mid-adolescence to early adulthood. Data came from three waves of the Swiss Survey of Children and Youth (COCON; N = 1,258). Bidirectional links between sympathy and mutual disclosure were tested with autoregressive cross-lagged panel analyses. Sympathy at age 15 was associated with mutual disclosure in friendships at 18, which in turn was associated with sympathy at 21. Multi-group models suggested that our model better describes these processes in females than in males.