A couple of posts ago, I mentioned that at a nutrition class, they said not to give children milk or juice in a sippy cup.
I think the reasoning behind that is to prevent cavities, it’s best to not let your child have a sippy to carry around all day with anything besides water. The sugars in juice especially would be constantly on the teeth, never giving the mouth time to balance its pH. Even though we only use 100% juice diluted with water, and usually only at breakfast, and milk at lunch and dinner, they were condoning having your child drink out of an open cup at meal times.
Aviana had been using an open cup forever, and then Brielle came along. She is much more of a ‘full-bodied’ baby, not at all careful, always reaching, grabbing, and spilling, so we used a sippy. Aviana now wants one all of the time too. And, when we are in a room besides the kitchen, if Brielle grabs Aviana’s drink, it doesn’t matter (and I don’t really like cleaning up constant spills in the kitchen either, but I’m not worried about the floors).