A child’s firsts tend to be magical days: their first steps, first words, first smile, and even first fit of the giggles.

The last one is the gift that keeps on giving, thanks to laughter's contagious qualities. This dad simply couldn’t keep it together when his 3-month-old son started laughing for the first time. There’s no word on what caused the baby to laugh in the first place—he is a newborn, so it could be just about anything (or nothing at all)—but once he starts to laugh, his dad catches on. And now neither can stop the giggle loop: The fact that the baby’s laughing is making the dad laugh is just making the baby laugh even more.

“I’m trying to stop!” he says to his wife while crying.

It’s an endless loop, and he’s powerless to stop it. Good thing laughter isn’t necessarily a bad contagion.

H/T Daily of the Day | Photo via nglau13/YouTube