He's only posted three times, he probably doesn't know how old cat-man is and, in my opinion, it has little difference as Stan was just addressing an error that cat-man wrote, I don't see what is wrong with that.
I thought "tripping" was used in the context of someone who has a false understanding - cat-man thought there were bearded dragons when actually there were not. I did not consider it to mean he was stoned - that would be a little out of context for an eleven year old!
