The Older Sibiling Complex

I have a theory: that older sibilings, no matter their age, gender, nationality or any other circumstances believe themselves to be always right.  Always.  I frequently exhibited this complex with my little brother, and with my parents, even though I knew that I was wrong and that I was not going to win whatever argument I was in.  Some may say that I was just stubborn.  Well, that's true, but I think that there might be something else too.  

When I came home on Tuesday from tutoring a girl in my neighborhood in English, I was approached by Estela, the older of my 2 host sisters about a translation.  I read the sentence in Spanish first, then translated the 2 words that she was having trouble with into English.  Now, Spanish and English, both being romantic languages, sound very similar, so translating is often quite easy and doesn't require a translator machine.  But, the other times when a word in one language is different than its translation in the other is strikingly different.  One of the words that she needed help with was one of those words. So, I pulled out my very handy electronic translator (which I highly suggest for anyone going to a foreign country for an extended period of time), and typed in the Spanish word.  Estela was not so confident in the translation, and asked me many times if I was sure of it's accuracy, which I was.  This has happened many times, and it kind of gets to me when she assumes that I don't know many words in my natural language.  This is the complex, one of superiority and self-assured accuracy and intelligence, and it isn't restricted to one country.