Understand that they live in a Joint Family but if you slightly change your perspective and look into each family individually like Mota-Bhai-Pariwar(MBP) & Chota-Bhai-Pariwar(CBP) separately the following analysis can be justified,
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CBP - As of now, the only earning hand is Ahem, as Parag lives on Mota Bhai's earnings.
and if Ahem continues to be irresponsible then Ahem will be Parag-Part II surviving again on his brother Jigar's earnings and then Gohem kids will naturally be left on the morsels thrown by Rashi, as she will not let them to come up in life and it's a different story although in that case Gopi will still feel that her Rashi ben does everything good for her and also for her generations to come'..
Hence the conclusion will be Ahem will continue to be Parag and Our Gopi will continue being servant to Rashi ben'.
Will you expect the MBP to feed the generations of Parag family.. if so how long then '?
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MBP - Mota Bhai is the one who is the head of the Modi Empire and legally Jigar will be his descendant. If the Modi Industries come under the hands of Jigar then imagine Gohem's life after death of Kokila' the two simpleton helping Jigar & Rashi taking care of Raji kids'..(Ahem is also a well-trained Dhobi now .. thanks to his MOM)'.
Why I say this is because you don't find any of Baa's siblings involved in MODI business, infact there is no trace of them'. And also how about Kinjal & Also the American Bua they keep talking about don't seem to be a part of the business too' they might have their shares but they are not the heirs to the throne'..
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Hence Kokila's concern is acceptable as a parents point of view... her hope of her generation being a part of MODI Industries is ONLY THROUGH AHEM''.
P.S. - Sorry for the long post...