ABIGAIL: Now, Betty, dear, wake up now. It’s Abigail. I’ll beat you, Betty! My, you seem improving. I talked to your papa and I told him everything. So there’s nothing to – .
BETTY: I want my mama!
– Arthur Miller
The Crucible, Act 1. Betty wakes from her mysterious sickness when Abigail furiously shakes her and says that she told Betty’s father about their antics in the woods. This suggests that Betty, who is afraid of Abby, has been faking her illness the entire time.