Because of the movie "the parent trap" I used to believe that I had a twin sister that my mom wasn't telling me about.
A childhood belief about family

others believed things like this
- I used to believe that every person in the world had a twin, and that I had a long-lost twin in France.— Ashley
- As a child, my twin sister and I used to pronounce `Spaghetti' as `Mastaghetti'. Sounds a bit rude, no? Anon
- My sister told me whenever I had a tummy ache it was my unborn twin inside my stomache trying to get out.— Jamie Field
- I used to believe that if you put your hand in a venus fly trap it would eat it.Anon
- I used to believe that my parent was actually stuffing me with tissue when I cut myself.— Colleen
- I used to think that you have to have the same birthday as your parent to have "junior" in your name.Anon