DH has OCD. It's not too bad, and it has gotten waaaay better since we started living together. Now most of his obsessions are gone (he still obsesses, but not to the degree he used to).
DD is obsessed about some things too, but I don't know if it could be normal 2 yo behavior. For example, her shoes need to be absolutely spotless, if they are dirty she will clean them herself. She has done this since she was very little. Her socks have to be perfect, too. If they bunch up or are not perfect she cries. I can't roll up pants or sleeves that are too long, she cries and unrolls them, and there can be no skin showing between her socks and her pants. It drives me crazy. I try to reason with her, or say: "We'll clean the shoes later," but she won't have it.
My older brother had to go to therapy to learn how to get dirty because he never wanted to get dirty, and DH has (had) the same kind of behavior.
My point is, does this sound like normal 2yo behavior?