Without a Drought

The kids were brushing their teeth tonight, and afterwards Allison filled a small cup with water. She had a couple of sips, and just as David asked me for a cup of water, she dumped out the rest of hers.

Me: Allison, don't dump that out! You're wasting water, and there's not enough water right now so we don't want to waste it. Do you remember? It's called a drought when there isn't enough rain.
Allison: Oh yeah.
Me: So you shouldn't dump that; David could have drunk it.
Allison: OK.
Me: Have you gone potty yet?
Allison: No, ma'am.
Me: Well why don't you try before bed?
Allison: But won't that make it even more droughtful?