A.J.
To be honest I don't think any sippy cup is totally spill proof more like leak proof. We have just been introduced to a cup that has a straw and so far they don't spill or leak really at all. They are from nubby and they have a short straw and you can get them at Super Walmarts or Frys I have been told. We also like the playtex ones that have the rubber stopper, the only time those leak is if they get shook really hard and then it is only a few drops
Good Luck
A.
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