I'd like to send my DD (still in a crib) to bed with a cup of water. We use Camelbaks during the day but they leak too easily for me to be comfortable sending them to bed with her. With my older DD we had some great Playtex sippy cups that never leaked, but the valves got gross and now they don't make them anymore. The new version has poor reviews. So help! I haven't really found anything else that doesn't leak.