The relationship between mental illness and the practice of naming a son after the father was investigated. Plank and Cameron suggested that individuals who carry their father's name often live under the father's shadow, and this might influence the social/emotional development of the individual. Previous reports of rates of mental illness among males named after their fathers were lower than the rate found in this investigation. Methodological problems might be the cause of this underestimation. Data from 1989 local birth records found that 19 percent of males were named after their fathers. Records from a western New York psychiatric hospital revealed that 19 of 110 adult male patients were named after their fathers. The findings failed to support Plank's hypothesis that Juniors have a higher rate of mental illness than the average population. However, there was a difference for affective disorders, i.e., the rate of affective disorders was higher for Juniors than the rate that would be expected in the general population. (LLL)