Over 30 years ago, my then 5 year old son came home from school one day and told me that they'd been learning about kings and Queens in class. I asked him what he'd learnt but he went red in the face, giggling and said that he couldn't tell me! I pressed him to tell me and eventually, convulsed in giggles, he told me that all Queens were "named after girls willy's "!
He finally managed to explain that his teacher had told them all that all Queens are known as Regina. And all the little boys in the class mixed up Regina, with vagina, and they all came out of school that day convulsed in embarrassed giggles! That took a while to unravel!