Impossible to Train

I can't even remember the event leading up to it, but as we were driving home today, my husband commented about something I'd done, ending with: "...You're impossible to train!"

Rising to the challenge, or perhaps daring to confirm his 30+ year old suspicions, I responded, "Too-whooo!"

To which, after a pause, he said, "You never laugh at my jokes. So why should I laugh at yours?"