is there anyone close to you but not related to you that...?

Question

you are so close to people think you are related? example: i have a friend, and we look a lot alike, and talk/think alot alike (more often than not we say the same things at the same times), and even present ourselves in the same way (i cant tell you how many times we start dancing randomly at the same time, or show up at the others house wearing the same thing). this started the second we met, so i know it isnt one of us immitating the other. is there anyone like that in your life?