(Make up for 11/17 discussion)
My brother and I are very different in terms of our personalities. He can be very shy especially when he meets new people. He's also not very open to new experiences, he likes to stay in his comfort-zone. On the other hand, I am very outgoing and love to try new things. In this essence, it can be said that my brother has an introvert personality and he is not the best person for agreeableness. But if I would take a self-report test, I would get high scores on extraversion and agreeableness.
The interesting part of this issue is that we are very different but we were raised in the same family with equal traits. Also, there is only 2 years of age difference between us which makes us even more similar.
I like Mischel's ideas about this topic, so I think that the situations might have shaped our personalities. In other words, our non-shared environments and therefore different conditions might have a huge impact on our characters.