In the episode, where Parag is fuming and throws Prem outside the house, Prem makes an accusation that Parag is responsible for his mom's death. At that point, Parag is stunned. Infact when his younger brother tries to explain/reveal the reason, he stops him from doing so. In that one scene, the actor who played the character of Parag was amazing in showcasing the transformation of emotions from being angry to being stunned. Even while being shocked, he is protective of his son and does not want him to know the reason. That scene was very well executed by Parag's character.
This scene has been playing on my mind and gives me two train of thoughts for her death.
I do not think Parag was cheating on his wife. He seems to be very devoted towards his family. He is a smart person and acute business acumen, but has blind spots when it comes to his family. He is not aware of his own SIL wrong doings towards his daughter. Always uses respectful tone and gesture towards Khayti. This makes me think/assume that he is not the reason for her death. So, here goes my first idea:
Depression: Gayathri like Prathana was very meek and could never share her thoughts. May be she was depressed that led to eventual death but not due to affair. I think Khayti make later in the picture. That is why he wants to protect Prem. Depression is very real and serious cause, I hope if they go this route, makers/create handle this sensitive issue very carefully.
Second may be I will pause on sharing, as that idea seems very unlikely to me.
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