Up until recently, four-month-old Leo wasn't seeing much of the world. It wasn't because he's four months old, but because he suffers from oculocutaneous albinism. "This affects the coloring of his skin, hair, and eyes and leaves him with extremely impaired vision," Leo's dad David explained on YouTube.

Shortly after receiving the diagnosis, though, Leo was outfitted with a pair of glasses. And he was able to see his mom, Erin, for the first time. Stick around for the whole 32 seconds to see Leo's second round of smiles.

Sources: Good Housekeeping UK