The way the first two seasons have gone, I'm thinking maybe it has something to do with the go cart trash guy's Nam photo or the two people in episode 2 who spoke up at the meeting (man and woman) that said something that didn't have at all to do with the kids.
I thought these first two episodes were very good. Purely plot-wise, I liked these two eps as well as I did the first two eps of S1. Hart's and Cohle's characters will be difficult to top, but this one has potential for sure.
Agreed with TheDeeble about the daughter and the wife and something not being right.
Edit: and at first the dad says be home by 5:30 and then be home before the sun goes down, which leads me to think there's maybe something deeper and more sinister