PokerStars 1/2 Hold'em (6 handed)

Preflop: Hero is SB with , .
UTG calls, MP calls, CO calls, Button calls, Hero completes, BB checks.

Flop: (6 SB) , , (6 players)
Hero bets, BB folds, UTG calls, MP calls, CO calls, Button raises, Hero 3-bets, UTG calls, MP folds, CO calls, Button calls.

Turn: (9.50 BB) (4 players)
Hero bets, UTG calls, CO raises, Button calls, Hero calls, UTG calls.

River: (17.50 BB) (4 players)
Hero bets, UTG folds, CO calls, Button calls.

Final Pot: 20.50 BB

I think the flop 3 bet is a solid play.

The turn call is kinda iffy because he's raising you after you've already shown pretty good strength. There are a lot of donks at 6 max who'll pull that stuff if they pick up a strong draw, but usually that means two pair or better, especially in a multiway pot. On the other hand, the pot is giving you decent odds (15-1 I think), so calling isnt a big mistake.

The river bet again seems fine. the only thing you're really afraid of here is a set. I might even check-raise this depending on the player.