In the kitchen scene with Joey and Danny in the episode "On the road again" (season8), Danny and Joey are discussing how you shoudn't tell kids what to do, as they would tend to do the exact opposite (think they're discussing weather or not to tell D.J not to see Viper anymore), and it comes up in their conversation that Joey once disobeyed his parents when they had told him not to eat mud when he was young. Joey had offcourse eaten the mud and gotten sick, and Joey says "let's just say I missed my high school prom"..... Anyway, what I'm surpised about is that Danny didn't know about it before Joey told him then, as they had been best friends since 5th grade and been in the same schools all throughout college and even dated the same girl in high school ("The heartbreak Kid" (season 6)), and they would definitely had hung out together (with their dates probably) on the night of senior prom, wouldn't they....?