A Common Situation - A series of donks

[wildzer0]

A lot of us make a decent profit from players who call raises OOP, donk the flop small and then fold to a raise. I usually don't need a specific read to raise the small donk w/ ATC unless the board's particularly bad or a raise will leave me committed (opponent is shortstacked). Here's a situation that comes up from time to time though that gives me a little trouble, here's a hypthetical hand.

Villain is 30/12/1.5 over a small sample (so fairly unreliable). He did make a small donk and fold in a similar situation 2 orbits ago.

Hero (Button) 100bb
Villain (BB) 100bb

Hero open raises 4xbb w/ A[img]/images/graemlins/spade.gif[/img] T[img]/images/graemlins/spade.gif[/img], BB calls

Flop: J[img]/images/graemlins/spade.gif[/img] 7[img]/images/graemlins/diamond.gif[/img] 6[img]/images/graemlins/diamond.gif[/img] (Pot: 8bb)
BB bets 1bb, Hero raises to 8bb, BB calls

Turn: 2[img]/images/graemlins/heart.gif[/img] (Pot 24bb)
BB bets 4bb, Hero?

Assume for sake of argument that hero calls

River: 2[img]/images/graemlins/spade.gif[/img]
BB bets 4bb, Hero?