I'm the oldest of 5 (born in 1985, 1987, 1988, 1993, and 1996) and even with that relative closeness, there were still a lot of differences between how The Big Kids and The Little Girls grew up - some of that was because of technology, some was Mom switching to overnights instead of evening shifts, some of that was the difference with getting outside babysitters versus paying your teenager (my parents paid me to babysit my sisters because they knew if they didn't I would get a paying job elsewhere and they'd have to pay one of my friends instead). What's been really interesting to me is watching the way that my relationship with my youngest sister has evolved over the years: 6/17 she was my excuse to see Disney movies in theaters, 13/24 I was her trusted adult, 21/32 we were the unmarried "bookends" who'd both experienced feeling "othered" from the rest of the group, etc. Out of my sisters and brother, I really consider myself closest to her these days. And also, yeah, I think it was probably a little weird for both of us when I was like "Heyyy, so I'm thinking about becoming a single mom" and she was like "Here are the things you should know based on my experiences being sole practical parent to a baby while my husband is overseas."

(I've also been lucky enough to land a therapist who's the youngest of 6 and therefore understands the way that Big Family Relationship Dynamics will fluctuate!)