Being a new parent can be an exhilarating — and challenging — experience. The seemingly never-ending diaper changes, the 3 a.m. feedings, and the fears of doing the wrong thing can take a toll. So ...

Babies can smile in the womb, even before they are born. A baby’s earliest smiles are reflex smiles, not an attempt to imitate or engage with adults. As babies grow, they develop more social skills ...