so I am not sure if I really understand the khandaan or the stolen jewelry logic here in this story but here are my thoughts. I wish we were watching ITV because it would be very explicity and properly laid out instead of us having to read between the lines.
I think this whole "khandaan" is just economic class bias. zainab and her family are obviously upper middle class but not rich. after her husband died, zainab was "in impoverished circumstances" (as how my favourite novels would put it). so she was economically down and without choices. that is why naima picked her. if she had picked a woman from their own social class of rich people for wahab, that woman would have automatically kicked out naima and wahab would gone on with a separate life. instead, naima wanted to remain head of the household. she can only do that with a woman who is emotionally respectful and financially without means to boss around -- zainab was perfect in that sense.
till naima got what she wanted, zainab's class wasn't an issue. zainab was willing to be second in the house and didn't see her as competition. she was a good second wife. now, naima sees zainab as a threat because she can see that wahab is also listening or catering to zainab more.
the whole khandaan talk is a way of putting zainab down and showing her to be someone as characterless. if it was sadaf or raeesa, I can see them stealing the jewelry. 🤣but this zainab and why would she steal from her own daughter? again, there is the issue that ushna is not her real daughter and therefore, trying to assert that zainab is a greedy woman who would steal from her own.
also shehroze had the impression that zainab only married wahab for money. so the idea that he would immediately doubt zainab is in some ways make sense. he was petrified that his mother would be kicked out and this mother-daughter duo would take over the house. naima is re-fueling those those fears. so yea, lots of fight ahead.
keeping aside class bias, the fact is that stupid behaviour exists in every class. what do people mean by khandaan really? grace under fire and a character of firmness -- that is about a person's inner being and has nothing to do with class. you can find such gold in every status.
ultimately, like renee said, this seems to be a love story really about a mother and daughter who stick up for each other even if they are not biologically related. that is indeed worth watching.