Angry-stomp-disconsolate

The oldest is in dire need of sleep. He stayed up reading in bed entirely too late last night. His eyes are filling with tears at the slightest provocation, and he's as grumpy as a hungry bear.

I'm used to the youngest feeling things more strongly, due partially to his personality, partially to his age, and partially to being sick. But the oldest is normally

happy-go-lucky
adjective
Taking things easily; carefree.
"happy-go-lucky." The American Heritage® Dictionary of the English Language, Fourth Edition. Houghton Mifflin Company, 2004. Answers.com 29 Mar. 2006. http://www.answers.com/topic/happy-go-lucky

I'm going to go pour him into bed now, I think. I bet he can't read for five minutes without falling asleep, especially if I warm his pajamas.