We introduced the sippy cup to DS a long time ago with water at meal time and he drinks from them very well. We decided to start the bottle weaning process as DS will be 1 year in just over a month. I tried putting formula in a sippy cup to give to DS and he won't have anything to do with it. The second he realizes it's formula he throws a fit and shoves it away. I know he can drink from the cup, but if it's formula he won't even bother. How can I get him to start trying it without winding up with a frustrated baby?