When I heard someone say, "mother-in-law", or "brother-in-law", etc. I thought they were talking about more than one person in general. I thought they were saying, "mother and all", or "brother and all", etc.
A childhood belief about speaking

others believed things like this
- I thought a major general is more powerful than just a general (which still kind of makes sense to me)— Demond
- My little brother once asked my mother when we past a couple of factories.. if the factories made clouds— nicky
- i used to think that mother nature was a real person— stephen s
- I heard a mother in the street tell her young son not to pick his nose...because his head would cave in. — Ruby
- I thought there were only four ranks in the army: private, corporal, Seargeant, and General— Alberto Richardson
- sophie b. hawkins. Damn I wish I was your lover. I heard Damn I wish I was your motherAnon