nts on a firm, safety-approved mattress; keep toys, pillows, heavy blankets and other loose objects out of the crib; tuck in a light blanket only up to the baby's chest level; avoid putting babies to sleep on quilts, sheepskin or similar soft surfaces; and never allow smoking around an infant.SIDS, the third leading cause of infant death in the United States, claimed more than 2,300 lives in 2006,