The investigators will conduct a randomized controlled trial within the 2015 Pelotas Birth Cohort. At the 3-month follow-up, children who sleep less than 13 hours per 24 hours (nighttime sleep and daytime naps) will be eligible for the study. The sample size was estimated at 276 children per arm. Nighttime self-regulated sleep duration will be evaluated at baseline (age 3 months) and at 6, 12 and 24 months using actigraphy and via a sleep diary completed by the mother. Following block randomization, mothers from the intervention group will be visited by a trained fieldworker who will deliver counseling on age-appropriate normal sleep behaviors, how to facilitate sleep onset and how to manage night awakenings.