When Does an Infant Start to Giggle?

Typical Timeline

• Cooing -- which is just chirpy vowel sounds -- and giggling are the two earliest types of imitation you'll hear from your little one. Your infant is likely to do both when she's 2- to 3-months old, according to Nickelodeon's Parents Connect website. By around 3 months, she's also likely to babble, imitating other sounds that she hears. By age 4 months, you can even try to have "conversations" with your infant by saying a word and then pausing, so she can babble an "answer." You should then repeat her babble, and then introduce a word instead.

Advanced Behavior

• Some babies come into the world ready for a good giggle. Little ones with advanced skills might actually learn to giggle and smile as early as 1-month-old -- although that's not typical, according to BabyCentre.co.uk. In addition to staring at faces and reacting to sound, advanced infants might also be able to hold their heads at a 45-degree angle at 1-month-old.

Slow Progress

• Keep in mind that not all children progress at the same rate. Children reach milestones, which are markers of typical child development like giggling and babbling, at different times. Most children should giggle, smile and squeal by 4-months-old, according to the KidsHealth website. If your infant isn't laughing out loud by 6-months-old, you might want to discuss your concerns with your pediatrician.

Additional Milestones

• Taking notes on your child's developmental milestones can be useful if you suspect there's a problem -- or if you just want to bring the notes to your pediatrician for reassurance that your child is on track. At age 3 months, in addition to giggling and cooing, you can expect your infant to smile when she sees you -- and begin to have a social smile for others as well. She's likely to enjoy interacting with others -- and be more communicative and expressive with her face and body than she was as a newborn, notes HealthyChildren.org, a website of the American Academy of Pediatrics.