THE DEEP END OF THE OCEAN. BtVS Intertext/Allusion.
In "Dead Man's Party," Joyce Summers' friend Pat unnerves Buffy with the following comment about her mother's emotional status while she has been a runaway (see "Anne"): "Well, between, uh, (exhales) your situation and reading Deep End of the Ocean, she was, uh, she was just a wreck. You can imagine."
Deep End of the Ocean was a 1996 Jacquelyn Mitchard novel and 1999 Ulu Grosbard film about a mother's emotional search for a missing child.