Read the excerpt from Flannery O'Connor's "The Life You Save May Be Your Own."

They drove back to the house to let the old woman off and pick up the lunch. When they were ready to leave, she stood staring in the window of the car, with her fingers clenched around the glass. Tears began to seep sideways out of her eyes and run along the dirty creases in her face. "I ain't ever been parted with her for two days before," she said.

Which best describes the irony in the excerpt?