Meredith: Promise me you'll kill me with lethal injection before I start to forget where my keys are.
Cristina: Of course.
Meredith: Early. Not when I set the house on fire because I forgot to shut the stove off or when I'm sitting in the rocking chair in the corner of the nursing home. I don't want my kids to go through what I went through--
Cristina: Mer, you had me at 'lethal injection.'