I experimented freezing cups of water that fit perfectly in the opening.
Each block of ice was slipped into a sandwich bag,
then all into a gallon bag. I didn't want them to stick together.
I had cold water the entire 90degree day.
I proved my hunch,
the colder the water the more the kids drank.
Yea, I was Biblical without nagging.
As a new believer, another cold water verse was introduced to me.