Aeschylus - - And even in our sleep, pain that cannot forget falls drop by drop upon the heart. . .

from Blog discussing "Blue Bloods" as a CBS drama series:

During the family dinner scene of this episode "Unbearable Loss," Frank Reagan (Tom Selleck) reveals that he has been asked to speak at the funeral and shares the quote that he plans to use –- a quote from Aeschylus’ Agamemnon (lines 179-183):

“And even in our sleep, pain that cannot forget falls drop by drop upon the heart, and in our own despair, against our will, comes wisdom through the awful grace of God.”

The main purpose of this reference, on the surface, is to convey through the evocative language of Aeschylus the intensity of the suffering and grief that accompanies a loss. Frank had intended to share this quote at the funeral of his eldest son Joe, who died in the line of duty, but couldn’t find the will to do so at the time. Now, by making use of this quote, Frank demonstrates his understanding and sympathy for the reverend’s loss through an expression of the pain and suffering he himself has gone through.

https://windswaves.wordpress.com/2016/12/14/the-awful-grace-of-god-blue-bloods-robert-kennedy-and-aeschylus-agamemnon/