Not toddler proof but pretty good!
Verified Buyer Reviewed by KingKid&I from Maine on Tuesday, May 10, 2016
My two year old and four year old daughters love their new water bottles! My four year old had no trouble at all, my two year old is still trying to figure out the straw, add in that you have to bite the nozzle to get the water to come out and it's a bit tricky for her. She's able to do it but sometimes gets frustrated then proceeds to squeeze the nozzle and spill water on herself. Overall the parts are easy to clean and assemble and so far we are happy with our purchase!