Today is my oldest sister’s birthday. Nancy is 8 years older than me, which is a relatively large gap. The other day I found this BuzzFeed that really nails our relationship:   http://www.buzzfeed.com/leonoraepstein/things-that-happens-when-you-and-your-sibling-have-a-huge   For the most part, it’s all true. We never ever fought growing up, she was very motherly to me when I…