The overall low recurrence rate of SIDS (< 2%) and the lack of concordance in twins are against SIDS being a genetic disorder. The most likely explanations for an increased incidence in siblings are that SIDS constitutes a mixed group of disorders that includes some genetic diseases and some disorders that are known to be recurrent but not genetic, and that some recurrences occur in families in whose lives there is severe deprivation, with many risk factors for SIDS, and in other families whose infant care practices, while not being overtly wrong, increase the risk of SIDS. With improving identification and management of these disorders and risk factors, it is expected that the incidence of SIDS, and, particularly, recurrent incidence in a family, will decrease. The best advice that can be given to families who have had an infant die from SIDS is that for most families the risk of another death from SIDS is very low (< 1%) and that if SIDS does recur, there will not be a prolonged period of suffering for the child. With this information and the recognition by most families that they do not regret having had the child who died, most families are prepared to welcome another pregnancy.