As it states on the YouTube channel, little 2 year old Zach loves dinosaurs, but has never seen one bigger than himself. This is his reaction.

He's happily running along when he freezes in his tracks at the sight of a T-Rex which looks to be downscaled but, to Zach, it doesn't matter. He freezes, the T-Rex locks eye on him as the family watches his reaction. I would love to know what was going through Zach's mind. Should he stay still like in Jurassic Park hoping he'll blend in if he doesn't move or should he flee in terror. He did what I probably would've done. He runs and tells his family to run as well.

Too cute.