She sees the snake coming long before it reaches her but she doesn't bother to move. She's not the kind of person that giant weird snakes are interested in; it'll be here for her siblings and they can take care of themselves.
It's definitely heading towards her, though, but that's probably some sort of mistake. She's not special or interesting or probably even a good bargaining chip. She's not worth anything.
But the snake comes right up to her anyway and she's confused instead of scared and then she's somewhere else entirely.
So she's dreaming. This doesn't happen to ordinary people.