Seems like sb is a weak player and i have seen him did similar weird smallish raises 3 bets with speculative hands. Definitely peels a lot preflop but i dont know generally how aggressive /passive he plays post flop

This is super weird with SPR remaining behind. Never really had this situation often enough to know what's best. Range wise it seems we should be betting smallish with our entire range here and with this hand we could pick up some equity and comfortably jam turn when we improved. Definitely didn't expect a check jam here and was sulking inside wondering if checking behind is better. Thoughts?