It seems that DD (just over 10 months) has self-weaned from her bottle. She has refused all formula since Thurs. I've tried sippy cups, but she won't drink formula out of it. I'm now worried about her water intake. I'm offering water all the time, and she has a sippy cup on the rug where she plays so she has access to it all the time, but she's drinking nowhere near the same amount of liquid as when she was on bottles. Should I be worried?