There's an 8 year gap between me and Skippy. We had VERY different experiences.

I study gene-environment interaction, so I teach about differences in sibling experience in class. The differences can be large, especially if there is a big age gap. Promotions, job losses, divorce, parental medical problems can all shift the world.

In class I use my own mother as an example. She was 13 years younger than her siblings, and the age difference straddled crucial differences in the lives of her family and the world they lived in.

My mother's sibs were born to an impoverished Swedish couple, struggling to survive in a strange and confusing new country, in a language they did not understand. The sibs learned English as quickly as they could when they started school. They were embarrassed by the stench of foreignness that they carried with them and did everything they could to hide it. Their father struggled to find work as the country descended into the Great Depression, and economic worries were constant.

My mother was born to a prosperous Swedish-American couple, living in a nice house in a middle class neighborhood. That house was dominated by two American-born teenagers who taught her English in the crib. HER father was a respected union carpenter in a union town who always had plenty of work in the mobilization for WWII and the economic boom that followed. She lived in a world of baseball and hot dogs and optimism, and she felt free to love everything Swedish because she never had to worry that she was not American enough fit in.

I tell the class that my mother and her sibs had the same genetic parents but very different phenotypic parents, and very different environments created by those parents. These kinds of difference can set kids off on very different life trajectories.

That's fascinating, Rick. I think now, my kids are a little like that -- my oldest was born when his father and I were still happy, and we were comfortable, financially. My daughter, twelve years younger than him, grew up not knowing any home but her grandfather's, which was rundown and depressing, and a dad who barely worked. My middle guy got to experience both.

That's so interesting, Rick! My mom's family was like that (she was the oldest and her brother was 15 years younger and my grandparents economic situation changed a lot over that time) and I always knew that his growing up experience was very different from hers but I never knew how to express it.

Very interesting, Rick!

Fascinating family history, Rick.

My sister and I are eight years apart and our childhood experiences were so different we might as well have had different parents.

My dad is an only child. He has two first cousins, siblings who are 11 years apart. The younger one is pretty close to my dad's age, and the two families lived near each other and were really close. That younger sibling says that she feels more like my dad is her brother than like her actual brother was. Her older brother was born in Germany, and lived there as a small child, but then spent ages 5-10 or so moving to a bunch of different countries as refugees, before finally settling in New York when he was 10 or 11. His younger sister was born in New York in the mid-forties. She grew up bilingual, while her brother had to learn English as a teenager.

I guess I'm the exception that proves the rule. My brother and I are 19 months apart, and our lives didn't go through any fundamental changes like those described above. But he and I are as different as possible.

It's probably genetic. I'm very much my father's son, and my brother looks more closely related to our cousins on my mother's side than to me. And our personalities take the same track.

My sister and I would be a fascinating study in Nature vs. Nurture. We are very different, about 5.5 years apart in age. Both adopted, no major changes in the family unit or financial situation during our upbringing. She knew we were both adopted, I did not.

There's almost 10 years between me and my brother (and 2 sisters evenly spaced between us). Between the time when I was born to the time my brother was born, my dad went from being a broke-ass law student to a pretty successful lawyer, so we grew up in very different financial households. My childhood involved a LOT more frozen fish sticks than his did.

Rick might enjoy this... my father is the second of eight. The kids range about 18 months to two years apart... the later the kids, the bigger the distance. The oldest was 16 when the youngest was born.

They grew up in the NJ suburbs depicted in The Sopranos and other than the actual Italianisms (a lot of it isn't properly Italian and my family isn't Italian at all) the oldest four basically have that accent... and the youngest four basically do not.

My theory is there was a population boom as the area shifted from truck farms to suburbs and the older kids were in a smaller more homogeneous peer group.

There was also a prosperity shift like P-moon's family as my grandfather's business grew and my grandmother went to work - the younger ones talk about spending the summer down the shore, the older ones maybe spent a week.