That’s what she clearly said when Sai makes vinu all right then she will take him ..
And Virat n kaku were present .. matlab she acknowledged that Sai will make vinu all right but still she is against this
That’s why kaku ke words to her were significant zz she told her Sai is vinu’s mother ( not ek Ma hai or Savi ki ma hai ) a mother will never harm her child .. in a way shading her ..
That you are purposely keeping vinu mentally Ill so that he stays with you ..it was like the Solomon’s tale