Firstly, interesting note at the end.My nine year old looking over my shoulder asked why "someone has a monkey picture on there". I had to quickly pull him away from the computer before KC could reach through the monitor and throttle him and then explain that it is an ape not a monkey.
He likes to watch Curious George while having breakfast in the morning and they constantly refer to George as a monkey when he is clearly a chimp....
Chimps have the biggest testicles of all of the apes...
Secondly, I'm with your son. They're all monkeys, just like KC's avatar.