My sister is almost 2 years younger than me. She is very different to me in many ways (interest in clothes, going out and she is very confident and outgoing in her personality whilst I am a bit more reserved, more of a homebody and make less of an effort with my appearance, gee I sound a bit dowdy...lol).
We pretty much ignored each other or fought madly between the ages of 14-25 but she is now my best friend! We speak every day and catch up at least once a week. I would be lost without her.