DS uses a rubbermaid sports bottle/plastic juice box type of thing with a straw instead of a spout...I could NOT get him to use a regular sippy cup for anything (I think it's because he didn't have bottles, and didn't get the concept of tipping his head back to get liquid), but he started using one of these things with water when he was about 7 months old....you can close the straw part to take it places, and unless it's totally full it doesn't leak when upside down (the straw opening is at the bottom so no liquid can get into it upside down unless it's full)...
Here's a link to the item, in case anyone is interested
http://www.rubbermaid.com/hpd/consum...rdMenuIndex=10
DH said, "He's not going to be able to suck through a straw if he can't use a sippy cup", and I said, "Oh yeah?" I filled the straw up with water a few times holding my finger over the other end, and then let it go in his mouth as he sucked on it, so he'd get the idea. He got the hang of it the first day, and we never looked back - so there, DH! HA!
Oh yeah, he finally does use sippy cups now, but only when I run out of clean sport bottles!
Oh, I don't know if these are 'safe' plastic or not

: , but we haven't had any issues.....
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