Sure, I understand. You've talked about the possibility that she'll get on fine with the girls 2 years older, but don't forget the possibility that she'll get on fine with the boys 1 year older (even if she shows strong girl-preference now). At DS's school there's some tendency for boys and girls to split into groups along gender lines, but not all of them go along with it. DS is one who doesn't, and doesn't seem to have had any trouble from this.

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