Two boys laughing while looking at a computer does not imply that one boy made the other laugh or that he did so by showing him a funny video.


Consider the statement "A younger boy wearing headphones with a microphone laughs with an older boy wearing a green t-shirt while looking at a computer screen.". Based on this "The boy at the computer made  the younger boy laugh by showing him a funny video" a true statement? Yes, no, or I don't know?