I think there are many people who wonder why Kokila behaves like this towards her bahu's..... which seems abusive by nature.......
Well......here is an explanation....
My mother used to say..... that in the olden times.... when the bahu's were merely small girls with a lot of play on their minds....... the saas used to spend the first couple of years or so training them........ like a potter...... moulding them into the desired shape...... My mother used to say that the new bahu is like the Mitti..... without shape..... and then the saas slowly shapes her......
So, they are made to work when it is play time........ when all the family is enjoying...... the bahu's have to sacrifice their own fun to look after the interests of the new family...... going out is always allowed only after taking permission from the elders in the family...... going to the mother's house is frowned upon.......
It seems like the saas is a dragon to the new bahu...... but slowly and gradually...... they learn all the customs of the household...... they also start loving the new family while away from their own...... The new bahu also understands that the saas does laad to her and loves her (without showing it to her)...... Just like Gopi knows that Kokila loves and dotes on her......
Even if there is a washing machine or maid in the house...... the bahu's are taught to do the housework so that they never fear the "bad" times if there are any....... also while they would be extremely lavish in all the things in life..... the saas would be very strict with the bahu to teach her to be thrifty...... again the rules that apply to the new bahu would be different from the daughter..... it is the saas who has to mould the bahu in the ways of the household..... which is why Kokila is OK with Urmila teaching Kinjal in her own way......
Its difficult for us to understand this possibly...... but people of the previous generation would identify with them and agree that its correct.......
If you note......Kokila or Hetal are "free" from such tortures...... but Kokila has made references to baa teaching them when they were new........ its the custom of olden Gujarati families...... and its not out of hate or power...... its about teaching them culture and values in their own ways......
Automatically, after some time...... the saas stops ruling over the bahu ...as the bahu learns everything and takes all the responsibility naturally on her shoulders..... the house runs smoothly...... and then they have an absolutely free hand with their time and money...... then they are not questioned..... Just like Hetal and Kokila.....
I hope this post helps......