As per my honest view; this story is very straight forward with it’s overall organ donation concept, which might make it little preachy. But the actual core strength is an emotional connections of characters and the many hidden psychological issues that story deals with. I knew that this story requires special emotional & kind of fairy-tale execution treatment. To make it small and tightened narrative; I kept it from Old man’s perspective and flashback events.
Story shows the psychological issue of an Old man. How he deals with his grief and guilt, and sudden acceptance of the Organ donation idea which initially he was opposing. Actually at Deeper level,  he thinks his Son who left them alone, is the reason that lead to Sarita’s demise. Moreover, in his old age and after getting separated form his son the only emotional support and reason to live the life was his beloved wife “Sarita” and at the end, he has to take decision to switch off her ventilator and let her die. This creates guilt and grief of loosing his wife, he seeks some kind of way to get back to her because of that his weak heart sank with pounding emotions and guilt he gets a heart attack and about to die but his son saves him by donating organs of his brain-dead mother. Which gives sort of a redemption arc to Son, and with heart transplant; Father (old man) also found a way to reconnect with his wife “Sarita”.