This story was written by Stephen King
Katie: It was someone in my own family.
Jeff: How do you know?
Katie If Billy called you up crying his head off, you'd recognize him wouldn't you?
Jeff: Yeah, I guess so.
Katie: (on the phone) Mom, did you try to call me a minute ago?
Katie's mom: No, why?
Katie: Oh you know how these phones are.
Katie's mom: I saw this dress the other day that...
Katie: Mom, I have to call you back.
Katie's mom: Are you allright, dear?
Katie: Uh no, I have a little diahrrea, I have to go. (hangs up)
Jeff: (laughing) A little diahrrea, that's great, I'll have to remember that when my agent calls.
Stephen King's short story of this episode, in script form, appears in his anthology Nightmares and Dreamscapes.