Causation conclusions gone awry

Saturday night PJ threw up.  He had caught the bug that AM had had a few days earlier (same symptoms and yes AM had also thrown up.  PJ was going to be home for a recovery day (he had a fever previous 2 days) and he came to me while I was making my lunch this morning and announced he thinks he know why he threw up.  "What's that?" I asked.  "I think it was the green beans."  Nice try PJ- it was the germs.  I hope this doesn't ruin his taste for them... one of the few vegetables he currently eats.