this is actually a pretty sick spot, right on the line...
Andees has a good point about setmining vs LAGs... truth is, their range isn't strong enough to properly set mine however...
LAGs can be spewy enough post flop to justify set mining if other callers come along for the ride. There are also other factors involved, namely the dynamic between you and the LAG. If you have been frequently clashing then I don't mind set mining here as that will add to the mix and dynamic you have... but if you are playing fairly snug then set mining isn't all that profitable for the reasons Andees mentioned...
As played, because he is younger and being awesome at the table and making moves and not making it to showdown, call him down.
flat the raise and check/call river.
If he is a "true" LAG then his range is going to be way wide enough with enough random KxQ
or A
J
or Q
7
type crap hands in it to make our call down +EV.
The more LAGgy he is the more we should just call down.
Also, in your OP you said he was a pretty LAG... but I'm guessing you meant to say "good" or "bad" but forgot...
that is also helpful...
but in general, the more this kid has been splashing around and raising, the more likely I am to just call him down and feel good about it. Give him the chance to be awesome and put your foot up his ass.