There's term for that. It's called "W" sitting, because the legs take on roughly the shape of the letter W. It's fairly common among young children. I suspect that I did this quite a bit as a child, and I still occasionally catch myself doing this now. I try not too, though, because I know that it's really not good for your hips. I know that I get random hip pain/ stiffness/ discomfort every now and then, and I suspect it results from frequently "W" sitting as a child. It has to do with balance problems, which I definitely have. I don't W sit often anymore, because I know now that it can cause physical problems, but I still sit in all kinds of bizzarre ways to compensate for my difficulties with balance.
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"And I find it kind of funny, I find it kind of sad./ The dreams in which I'm dying are the best I've ever had."