Train Inspectors?

I have realized that it is okay that I don't always understand my children when they talk to me. The pronunciation of certain words definitely is a tough task for Jay but luckily I have
Chance to tell me what he is saying.
Jay was very persistant in trying to find out what I thought him to be saying as train inspectors. What are they? He kept asking me.
Clearly me eldest son noticed I was getting frustrated with the question due to the UGH, what are you talking about look on my face, the baby in one arm, and my other hand trying to make cereal, and he yelled out to me, "Tranquilizers, he is saying tranquilizers!"
Was Chance actually put out by all the commotion? Appearantly, because as soon as he said his piece he picked up his book and huffed down the hall and I distictly heard the bedroom door shut a little harder than usual. He is 9 now ya know and he has no problem reminding me!