By Wond PregThe safest sleep environment for a baby can be remembered by “ABC” – Alone, on their Back, and in a Crib. To elaborate, this means babies are safest in a flat crib (or similarly firm sleeping surface) with only a fitted sheet – no pillows, stuffed animals, crib bumpers, fluffy blankets, extra humans, etc. A wearable blanket, sleep sack, or thin blanket swaddled around the baby is okay.