NL100: KK oop, A hits turn line check

[Artsemis]

PokerStars Pot-Limit Hold'em, $1.00 BB (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

CO ($100.85)
Button ($99)
SB ($55.55)
BB ($79.60)
Hero ($102.30)
UTG+1 ($75.20)
MP1 ($96.50)
MP2 ($29)

Preflop: Hero is UTG with K[img]/images/graemlins/diamond.gif[/img], K[img]/images/graemlins/heart.gif[/img].
<font color="#CC3333">Hero raises to $3.5</font>, UTG+1 calls $3.50, <font color="#666666">4 folds</font>, SB calls $3, <font color="#666666">1 fold</font>.

Flop: ($11.50) 9[img]/images/graemlins/heart.gif[/img], J[img]/images/graemlins/club.gif[/img], 2[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
SB checks, <font color="#CC3333">Hero bets $9</font>, UTG+1 calls $9, SB folds.

Turn: ($29.50) A[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">UTG+1 bets $6</font>, Hero calls $6.

River: ($41.50) 3[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">UTG+1 bets $18</font>, Hero calls $18.

Final Pot: $77.50

[ClubChamp04]

I likely fire the turn. Checking puts you in a bad spot and leads to problems.