For the past few months, your little one was cushioned in the dark confines of your uterus, where she listened to a never-ending whooshing, thumping playlist and was rocked every time you stepped away from your desk to make a photocopy. So it should come as no great surprise that she still isn’t entirely acclimated to the big, cold place that she was recently thrust into.

For now the best recipe for a peaceful baby is to do everything you can to remind her of her last pad: the womb. “Start by thinking of your baby’s first three months of life as the fourth trimester,” says Parents advisor Harvey Karp, MD, pediatrician and author of The Happiest Baby on the Block. Why? Mimicking what she heard, felt, smelled, tasted, and saw in utero can turn on her calming reflex and help her feel safe and secure — so she’ll cry less and sleep better.