[JCThoughtscream]

Article says near the end that their communicative abilities are limited to badly enunciated short sentences. AND they're four years old. Four years old tend to ignore difficult questions in favor of something more fun.

[scott_s]

It's not just that they ignore such questions, such questions don't mean anything to them yet.

Something else I thought about was the supposed tendency of identical twins to have have a pseudo-dialect between each other. Perhaps these two don't communicate with the outside world as much because they're too busy communicating, silently, with each other.