Not only kids. I would have to look for the papers, but there are enough behavioural studies on how people react when given alcohol. Many people start acting drunk when told that there is alcohol in their drinks, regardless of that being true. At the same time they do not act as obnoxiously drunk when given alcohol without their knowledge. The typical slurring of speech, loss of coordination and associated physical effects come into effect, but the behavioral changes are weaker. Up to the point where they realize they are drunk.

This together with the studies of drunken behavior across the globe has lead some researchers to posit the hypothesis that the behavior while drunk is more of a cultural effect, based on how the culture expects people to act while drunk.