When HM got cancelled because Neha was unhappy, do you think future of Devakshi is safe in Ishwari Nivas. Every day Neha would be upset because she couldn't figure out her priorities and more so because she has a mother who never finds time to sit and talk with her daughter. Mother is always busy planning on how to keep Sona out of Dev's life's priority list. Who knows tomorrow she may insist Dev on leaving Sona just because Neha feels unhappy seeing the couple having romantic time together. Neha never got good advice in her entire life. She is still a child who needs love but circumstances and neglectance of Ishwari till date had made her into tantrum child. She needs a mature person to talk to, someone sensible like Sona, who can help her understand the basic values of life on short and long term. Till now Neha always thought of short term happiness, Ranveer's love only can make her happy lets get married, Ranveer doesn't earn much, lets get divorce. She never thinks logically, thanks to her crappy mother.
Only Sona can help her in the entire family. Rest all apart from mamaji and Dev are idiots and selfish people. And If left on dixits to solve the issue, Neha will be divorced a day before not a day later.
Ishwari had just one motive behind of not asking Sona to get into this, If sona ends up solving the problem which Ishwari thinks she may, Ishwari will loose her control over Neha and Dev.