Usually I would agree that changing name is regressive. But in Sais case it has different meaning. Until now her not taking Chavhan or Viraat name was because she thought her status in his life was temporary. Now he is just as important to her as her Aaba. So she wants to be associated with his name. She has her name Sai which is her aabas nishani, middle name of Viraat who is important part or rather her life & with Chavhan name she gets a parivar which she lacked with name Joshi.
Virat takes up Sai’s name as he too wants to feel same association with her. With keeping Chavhan name he can argue that he is still CN ka beta & that’s why Sai CN bahu.
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