How to Tell When You Need Sleep

So... I made a bottle for little man the other day right before he woke up from his nap. It wasn't quite time for him to wake up, so I put the bottle up until then. When he did wake up, I went to the fridge, where I was certain I had left the bottle.
No sign of it. I checked my room, where I had been folding clothes.
No luck there.
I checked the living room, where I had stopped to read an article. Nope, not there.
I checked the sink, thinking, "Maybe I gave it to him earlier, and I just thought it was for after his nap."
Nope, nothing.
Finally, I gave up and opened the cabinet to get out a new bottle.
Yep. There it sat.
Full.
Spoiled.

DUH!!!!