Sai is making emotional decision based on her love for Devi and blind trust on Pulkit. Kaku could just play her like fiddle, even yesterday. Sai couldn't handle Kaku without Virat in past 2 weeks.
She saw first hand how Devi's condition deteriorated in just 1 day and how kaku put the blame on Sai very easily.
Virat is making informed decision based on whats in front of his eyes/ evidences/ based on life experience. (he fell for emotional decision on Shiv Ratri, but letter and fake evidence put a stop to it).
No matter what, Kaku eventually gives in to Virat's logical argument. His decision is kind of final in many situation. So him doing something vs Sai doing something is not the same.
If Devi was of sound mind and she wanted Sai's help in eloping, that is different from taking a life changing decision that impacts a mentally unbalanced person's life just coz she feels like Pulkit is trustworthy.
Did she think how it will be for Devi to live with her husband suddenly or if she finds she has 8 yr old daughter? What if it further creates issues?
How does she know for sure Harini is Pulkit's and Devi's daughter? How is she so sure Pulkit is a good guy?
Will we let 18 year old who knows nothing of the past to make such a life changing decision in our home based on their beliefs? Forget bahu/ damad, if my 18 year old cousin tries to do something like this with their own life, they will be blasted left right and center.
The very fact that she has to resort to a tactic like elopement means that she has no right to get them married.
Virat could announce it in front of the family means he has the right to do it. Even if family opposes it, he could still make it happen.
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