Babies start smiling around 6 to 12 months of age.
Even shortly after the baby is born they may seem to smile some but it's usually not a real smile or meaning of a smile.
Eventually the baby will begin to smile when they see something they like or when they see their mother or father or someone else they love.
Even toys can make a baby smile.
A baby's first laugh will usually begin around one month after their first smile.
Though 4 months of age is a common time for a baby's laughter to emerge, it could happen at 5, 6 or even 7 months old.
Babies also love to imitate facial expressions, so the more you smile at your baby, the more he or she is likely to smile back at you.
By responding to your baby's smiles and engaging with your baby in this way, you'll be encouraging his or her development.