$50NL on party.

2 limpers to me and I limp with 44. Button limps and sb min raises. BB folds and everyone calls. SB has $14.

Flop comes [ 5s, 6h, 3h ]

Checks to me and I bet $4. Button calls ($72 and I have him covered) and SB goes all in for almost $13. Little more than $8 to call here. What do you do? Button is semi tight but not a great player.

Fold. SB could have two high cards (something like [Qh]) or a medium to high pair (with a backdoor flush draw). Button could have a set made or drawing to a straight or flush. Even if you have the best hand right now it's unlikely to hold up and you don't know what Button is up to. Suppose you call and he decides to push? This flop is way too dangerous. There are a million ways for you to lose a lot of money. Get out while you can.

I raise to get HU against the shortstack.

If the SB is a typical monkey of a short stack, he could have any two cards. But I bet he has a real hand and you're behind him. So I don't like the push. If you call, trying to get better pot odds by bringing the other guy along, if he does chase he may have a flush draw, killing some of your outs. 6 outs twice isn't enough 3 ways. I fold.