A baby is going viral on TikTok for his hilarious reaction to learning Dad has a twin — and viewers are cracking up!.The video — originally recorded by dad Stephen Ratpojanakul — was recently uploaded to TikTok by the channel @brotherhq, where it quickly gained millions of views.If this hilarious footage looks familiar, it might be because the video has been making the rounds on social media platforms for the past 5 years — .but this is the first time the video has gone viral on TikTok.According to a 2016 interview, Stephen explained that his baby, Reed, had no idea Dad was a twin — until Stephen's brother, Micheal, babysat.Reed, only 16-months-old when the video was shot, had never seen the twins in the same room before, and couldn't quite figure out what was going on."Reed isn't used to me wearing glasses, and in his confusion he kept reaching back and forth between me and Michael," Stephen explained in the interview.Given its popularity, the adorable video has no shortage of comments from all over the world."Why is this so cute?" one user mused