An overdeveloped sense of irony

Sometimes it's not so easy having a kid who has a sense of humor. For one thing, it's nigh impossible to get a straight answer out of him.

Me: Wild Thing, who did you play with at school today?
WT: Nobody. (Smiling)

Now, I know that's not true. WT isn't the most social kid in the world, but he has a small fan base there that won't leave him alone. I continue:

Me: Nobody? Really? That sounds lonely. Did you have fun?
WT: No! It was terrible! (giggling)

Now, it's quite clear that he's pulling my leg and that he had a fine time at school. But it leaves me entirely unilluminated about how he spent his day or who he likes to play with.

I'm starting to think that my son suffers from RID--Relentless Irony Disorder.