OK, this is a true story, and it hinges on a false cognate.
When I was in my late teens, I was traveling on a bus tour through Andalucía. There was a tour guide on the bus who led us through various historic and tourist locales. He had a pretty American girlfriend along on the trip who spoke fairly good Spanish and was eager to use it at every opportunity.
When we came to Seville, the tour guide's home town, he took her off during our free evening to meet his family. The next day on the bus there was a rather uncomfortable silence between them, and a nosy Spanish woman got up the nerve to ask the young woman (in Spanish, of course) if they had fought and what had happened. The young woman replied that she was angry with her boyfriend because "Él me embarazó delante de su familia." She thought she was saying he had embarrassed her in front of his family, but in Spanish it has rather a different meaning, namely, "He impregnated me in front of his family." I immediately recognized the error she had made and burst out laughing before I could stop myself. The Spanish busybody gave me a glacial look and said, "Y tú, sinvergüenza, ¿de qué te ríes?" ("And you, shameless one, what are you laughing at?")