  John and I have come to feel that we made a big mistake in our parenting method and now we're trying to rectify it. We always thought we'd treat the kids equally, on an equal level, and they'd both answer to us and never to each other. We never encouraged Aidan to hold Ellie, instead we tried to often hold them both on our laps together. I should also admit that I was always bothered by the sight of little girls nurturing dolls. My feelings regarding the nurturing desires of little girls first began to shift after studying instinctive mothering among humans in developed and primitive societies, as well as those of other primates. Socioanthropologist Sarah Blaffer Hrdy explained in Mother Nature that the mothering instinct is tied to social ambition necessarily because over thousands of years of human development, the children of women who were best able to position themselves in the culture group were most likely to be cared for, and thus survive.
Where I used to fear these little mommies would never want more than a child out of life, now I feel that a child exploring her mothering desires goes hand in hand with preparing for an ambitious life. I was also greatly changed after reading what I now feel is one of the best parenting books ever--Margaret Mead's Coming of Age in Somoa --and now continuing on to Growing up in New Guinea .
I really respect the method of letting older children mind the younger ones. Mead explains it as when a child gets just old enough to be so willful that they're driving everyone around them nuts (and this age correlates to five or six), they're saddled with the huge responsibility of minding a newly weaned (at 2 or 3) toddler. The society is structured so that kids want responsibilities, as that's the only way they get to take part in adult expeditions or be around adult cultural life. I think our society's automatic promotions based on age (like when you're 5 you go to school, when you're 7 you can be in scouts--or whatever) might be harming our kids who are wired to progress in behavior based on societal incentives.
In lieu of incentives, what makes our children want to behave? Anyway, Aidan's now "in charge" of watching Ellie quite often, and he's blossomed in light of this new job. He's very caring. Yesterday at the park he jumped in front of a bullying kid and said "don't push my sister! " He's big enough now to go into the kitchen, get a cup, and fill it with water, which he does for her all the time. Remarkably, Ellie eats better when Aidan feeds her than when anyone else does. This was a big jump from our previous position in which he was never allowed to feed his sister food, for our fear that he would give her something dangerous. Ellie often just wants to sit in someone's lap, and now I've found an extra lap for her to cuddle in during Telletubbies or a book. When she's hurt, his response was often one of indifference and in our effort to teach him empathy we made him come take part in making her hurt better. That process is much more automatic now in him when he realizes he can actually make her better by himself. He wipes her tears and says, "that's all right, Ellie. " I still catch him being indifferent sometimes, but we're working on it.
I've always wondered at their very close relationship. Aidan spends more time with her than anyone, aside from me. She worships him, and it's very natural to me--after changing my point of view--that she responds so well to his care. The best expression I've gotten yet was on one of the first days we tried this. Aidan told me, "I'll take care of Ellie mom, you should go take a shower.
" I almost fell over laughing because when John's home that's my big treat. Since the peace only lasts about 10 to 15 minutes right now (b/f John or I are needed to settle some issue in Aidan's parenting tactics) we settled instead on Aidan watching Ellie while I laid down in my room to read my new New Yorker. It was still very nice. 
