If you have blond hair, that simply means you were born with blond hair. People associate blonds with being dumb, though, and that's why people joke about blonds a lot. I think the term 'dumb blond' came from ... Well do you ever notice how the really popular girls at school a lot of times are blond? I'm not stereotyping, so please don't take this the wrong way, but the popular girls are those who usually prefer beauty over brains, which is fine. So they don't really spend much time studying, rather they spend their time on hair and make-up, etc, to make a good and lasting impression. So when the smarter people ask them complicated questions, they don't know the answer. Then people start teasing blonds over their "ignorance", it becomes a big deal, and now some blonds even act ditsy to get attention. But yah, I'd say that's where 'dumb blond' came from. But really, don't worry if you are a blond, because if people tease you, you can always prove them wrong by showing them you are not the 'dumb blond' type. Lol ^^