Even though I haven't played, as I'm only just starting to act on my long time desires, I see my self as two possibilities:
1. Young child - About 4-6, I like cartoons, Lego, K'Nex, etc. A stubborn tomboy girl who still needs mommy/big sister to bring her into line and sometimes, particularly with big sister, that means treating their baby girl like a baby - regardless of how much of a fuss she makes.
2. 19 - my actual age. I struggle with depression, and I often think a mommy/big sister to care for or punish me as they see fit would help. If nothing else, it might help my habit of procrastinating.