"He wants me to tell him a story. I can't." Krishnan's voice is a rasp as his throat is slowly but surely caving in. "Will you ensure he remembers me when he grows up?"
That's when the first tear rolls off your face.
And they don't stop after that. They don't stop when the movie ends, they don't stop as you're embarrassedly making your way to the parking lot and fighting the urge to inconspicuously look up and check if others are red-eyed as well or if there's some problem with just you, and they don't stop for a long part of your way back home.