Here's some context from the movie Winter's Bone (2010):
Merab: Thump knows you were in the valley, child. With Megan. And at Little Arthur's. He knows what you want to ask, and he don't want to hear it.
Ree: And that's it? He ain't gonna say nothing to me?
Merab: If you're listening, child, you got your answer.
Ree: So, I guess come the nut-cutting, blood don't really mean shit to the big man. Am I understanding that right?
Merab: Don't you dare. Don't! I want you to listen to me, child. You need to turn around, and get yourself on home. Don't you make me come out here and tell you again!
What does come the nut-cutting mean here? Is saying come the nutting the same as saying if the nut-cutting comes? I don't really understand the way the verb come is used here. Any help is much appreciated!