Let me tell you all what's going to happen.
Let's start with Aarohi. Aarohi will give birth and become a single mother. She will then remarry Neil's look alike ,get pregnant and give birth to her second child. Both kids will believe the 2nd husband is the father until the truth about Neil being the first child's father. The 2nd child will start feeling insecure and will disliking his/her brother.
Akshu on the other hand will raise her child alone away from family. Then maybe she or the child will fall sick and will end up meeting the Birlas. After some episodes, Abhira reunion will happen.
Then at the end, Akshu will fall from cliff and die(must continue grandmother's and mother's legacy) The 2nd husband will also die and somehow just the way Aarohi blamed Akshu for Sirat's death, her 2nd child will blame her firstborn(Tum ne mera papa ko cheena, I hate you). Aarohi will then try to unite them but will fail. She will realise she was wrong to blame Akshu for Sirat's death. In her haste to meet Akshu, she will slip from stairs and die or maybe she will die in any mandir. Kairav will mourn both sisters dead and will completely disappear
So conclusion, Aarohi will die like Sirat, Akshu will die like Naira and Kairav will vanish like Naksh. The 4th gen track will start. But since Sirat and her kids aren't legacy, probably their track will end. Shivu will become a mix of Kairav and Vansh. Birla family will become main focus while Goenkas will dissappear. A new family will be introduced and the saga continues....
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