Dark humor (21++)

One time, when I was at dinner alone, I overheard a big fat guy trying to tease the diner's owner. From the look maybe they know each other so well.

Big Fat Guy (BFG) : Hey Kid, did you ever woke up at midnight and found that your dad are punishing your mom on bed?

Owner's Kid : *silent*

Owner : Don't try to teach my kids something nasty please.

BFG : You know your dad often punish your mom when you are asleep. So, when you heard your mom shouting at midnight, don't hesitate to wake up and punch your dad. OK?

So, the big fat guy was having dinner with his son as well and he looked a little bit confused.

Poor BFG son : But dad, I often see you slapping mom with your little wee-wee. Should I do the same too?

Me and other guest were laughing.