S.R.
L.,
I too have OCD, my youngest daughter is also showing traits. However, I do not think hand washing is one of them. My youngest boy (who is far from OCD), loves the water, he would play in the toilet if I let him. So he goes to the sink all the time. He makes up reasons, like if I give him a bit of my Ice cream, he says done & I wash up now. He did not need to do this, just likes the water. I have a pool, and am very blessed for it, and I put them in it as much as possible, the water is something all my children love. Try giving her a pool, even if it is just a kids pool, let her get to the water more often. See if that helps, giving her this access may lessen her desire to always play in the sink.
Now that I have given you my 2 cents worth of oppinion, I am also going to tell you, I think you should talk to your pediatrician. It's never to early to monitor behavior, it could be OCD, it does come in soooooo many different packages.
Always eliminate all possibilities of medical issues, whenever you can.
Good luck & let us know how she does.