Originally posted by: anaamica
I dont think NK can live with the truth that Kunal is not his own blood. He is too proud of his Chauhan khandaan.
Once Nirmala got Sandhya into the house, Sandhya might have used her charm and skills to win NK's trust. She is like NK's right hand now, so NK wants her in the house.
I think she is the one responsible to create a rift between NK and Nirmala. She put Nirmala down in front of her husband to increase her own value in the house.