To determine whether sleep problems commonly seen in pediatric practice, such as conflicts at bedtime and night waking, are associated with more pervasive disturbances in the child or family, two groups of healthy children were studied. Interview data from a pilot sample were examined to identify factors that might be important in sleep problems, and then the results were validated with data from the second sample. The two samples included 96 white children between 6 months and 4 years of age. In each group, approximately 30% had a sleep problem by the criteria that night waking involving parents or bedtime struggles occurred three or more nights a week for the month preceding the interview, accompanied by conflict or distress. Five experiences distinguished children with sleep problems from those without: an accident or illness in the family, unaccustomed absence of the mother during the day, maternal depressed mood(s), sleeping in the parental bed, and maternal attitude of ambivalence toward the child. These experiences correctly classified 100% of pilot and 83% of validation sample children as having a sleep problem or not. The similarity of findings in the two samples attests to the potential importance of sleep problems as an early childhood symptom. Bedtime conflicts and night waking seem to be quantifiable, easily ascertainable behavior patterns that could alert pediatric health professionals to the existence of more pervasive disturbances in child and family.