I once heard that babies don’t actually smile because they’re happy. Instead, their raised cheeks and exposed gums were actually just involuntary facial movements no different than a kicking leg or a flailing arm. In fact, I remember one relative telling me that a baby’s smile was more likely a result of him or her passing gas than being pleased. It made sense, and I never questioned it again—until recently. My boyfriend’s four-month old nephew is the happiest baby I’ve ever seen, and when you really get him excited he smiles from ear to ear. His whole face lights up and his dimples show up as he watches you with utter amazement. I thought these facial movements simple couldn’t be involuntary, so I decided to look it up. My family was completely wrong, and a baby’s smile is in fact an indication that he or she is very pleased.

Most babies start really smiling when they turn two months old. At that point, their facial muscles are developed enough to move on their own, and their cognitive development is far enough along to pick up social cues. However, some studies show that babies have even smiled on ultrasound images while still in the womb. They suggest that these embryonic smiles are likely a result of the pleasure a baby feels when falling asleep or waking up.

Sometimes, your baby might smile just because you are smiling. Research shows that babies are evolutionarily predisposed to copy the facial expressions of adults so that they learn the culture and environment at an early age. Much like listening to a language, a baby will watch his or her surroundings intently to learn how to act. Though, there will also be times when you can send your baby into a giggle fit by doing something outrageous. If you notice your baby smiling but turning away from the fun, give him or her a break. This is a sign that he or she is over stimulated, which could cause frustration and tears.

There are few things better than having a baby smile at you, and as a new mom you’ll finally feel as though all of the aches and pains of pregnancy were worth it. Your baby’s smile is not a result of gas. It is truly a sign that he or she is having fun, and it’s a clear indication of brain development.

Source: Daniel Messinger et al: “Are You Interested, Baby? “ Young Infants Exhibit Stable Patterns of Attention During Interaction. Infancy Volume 17 Issue 2 pp. 233-244 April 2012

Keyword Tags: