PokerStars - $0.10 NL (6 max) - Holdem - 6 players
Hand converted by PokerTracker 4: http://www.pokertracker.com

CO: 133.9 BB
Hero (BTN): 104.2 BB
SB: 100 BB
BB: 100 BB
UTG: 118.1 BB
MP: 100 BB

SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 1.5 BB) Hero has As Jc
fold, fold, fold, Hero raises to 2.5 BB, SB raises to 12 BB, fold, Hero calls 9.5 BB

Flop : (25 BB, 2 players) 9h Ah 6s
SB bets 7.5 BB, Hero calls 7.5 BB

Turn : (40 BB, 2 players) 9s
SB bets 12 BB, Hero calls 12 BB

River : (64 BB, 2 players) Qc
SB bets 20.5 BB, Hero calls 20.5 BB

Q1. Was this call down acceptable?

I think we are at the cut off point with J kicker so borderline acceptable.

Q2. Does villains sizing for 3 streets change things?

I think its unlikely I will win by river bet and he is wanting me to call.

Q3. Should i ever fold the river? What stats info could be used over large sample to aid this decision?

I'm uncertain.

Q4. Would this have been a better hand to 4-bet due to blockers?

Yes, but I don't know if things change on the button. I would fold to shove after 4-bet.