My brother is my half-brother from my mom and my sister is my half-sister from my dad. When I was young my brother told me he was more my sibling than my sister because we had the same mom. I believed him for the longest time!
A childhood belief about family

others believed things like this
- First I believed that my parents were brother and sister. Then I thought that my dad was also my mums dad. — Rainbow
- I used to believe my parents were brother and sister, and that everybody's parents were brother and sister.— Rachael
- That you had to marry your sibling. During this period of time I devoliped a crush on my brother.— don't worry I'm a girl
- I used to belive that my mum and dad lived together cause they were brother and sister— Corin
- I used to think that Cain and Able were brother and sister (with Able being the girl).— Duh
- I used to think Jane Austen was related to the Bronte sisters, maybe like their cousin or step/half sister.Anon