I think it's safe to say this is the best reaction to finding out you're going to have a sibling since Cain saw Abel being born and famously proclaimed:
When the little girl in the video is told by her father she will soon be a big sister, the 3-year-old quietly ponders this news for a couple seconds, then leans forward and whispers:
It's one of those moments in history, like the fall of the Berlin Wall or the release of the first "Hunger Games" movie, that just changes our world forever.
The best thing is that the parents were videotaping the event in order to document something heartwarming and beautiful that they could gather around and watch together for years to come.
Too bad, guys.