The ghazal she used talks about raaz - the walls have ears and to talk softly. So someone is going to overhear.
If Kv does, he may feel the cringe that Abhi will be his own son’s mausa. So he may share - even recently he was asking why Abhi is marrying Aarohi. So if Kv knows he will tell Abhi.
Plus if Muskaan blabs KV will most likely overhear.
Ripping Abhimanyu apart will be Kairav's first reaction I agree, but Akshara will ask him to think what good will come out of that. Arohi will be left at the altar again and Ruhi without a father. Abhimanyu will fight for custody and Akshara will not want Abhir to go through the torture. She will make it clear that Abhimanyu has no place in her life at all.
She is happy and is/has moved on in her life, she will request Kairav to support her and let things be the way they are. If Akshara had still feelings for Abhimanyu may be Kairav would have still told Abhimanyu but now he wont. He will respect Abhinav more and detest Abhimanyu even more.
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