Laughter is known to be the best medicine for just about everything, and for good reason. Aside from protecting against heart disease [1], laughter actually works to foster brain connectivity and cultivates relationships with others. So it's no wonder that parents eagerly await the big milestone [2] of watching their little one let out a genuine laugh [3] for the first time.

All children are different and reach milestones at various paces, but a baby typically starts giggling and laughing [4] in response to tickles, silly faces, or even bouncy movements by the time they're 4 months old. Don't worry if your baby doesn't start guffawing away at such an early age, though, as it isn't unusual for some to wait until they're almost a year old before they have a true belly laugh. Plus, sometimes it takes parents a while to figure out how to get their little one to laugh out loud (remember when Ross sang Sir Mix a Lot's "Baby Got Back" to make Emma laugh [5] on Friends?). Just remember: be patient and enjoy the moment when your baby does starts laughing, because before you know it, they'll be rolling their eyes at your bad jokes.