S.B.
Hi Julie
I have had the same problem with my sippy cups where they start to leak when my 1 year old son uses them. I was fond of the playtex sippies untill recently when they started to leak and the rubber mouth pieace started peeling off and I found that it wasnt safe anymore.
so I was in cvs with my sister talking about some sippie cups and she pointed out the playskool sippies which are hard plastic all around and even the inside valve was hard plastic not rubber and what I loved was you can choose fast or slow dripping so that the sippie doesnt leak, and I found that now there are less leaks
and more drinking which is wonderful, I also like the way the handles are on the cup instead of the sippie mouth pieces and you can take the handles off the playskool one if you dont want it unlike all of the others this one is switchable , so maybe you would like to try those instead ....
Good Luck :)
Happy Holidays