So my theory goes like------
DB had an affair with Oberoi's daughter before he gave his promise to SP. He might've told it to his GF. As his gf belongs from elite family, she might've hide her pregnancy. Maybe Oberoi's also knew it thus enmity gets created from there. Kabir might've born without wedlock & Oberoi's daughter might've died while giving birth to him. Thus Oberoi's took responsibility of Kabir, treated him better, loved him as their own blood.
When Kabir might be 8/9 years old, Oberoi's heir got born which is Neil ( might've different name ). Kabir being elder brother was happy along with Oberoi's.
Meanwhile Shobana might've got to know about DB's affair. Hence she secretly took the charge & tried to eliminate Oberoi's. She thought that it had became successful but there might've a twist. When Shobana came to meet them, Neil's biological Mom might've sensed something. Hence, she told Kabir to run away along with 1 week old Neil. When Kabir got news of it, he was heartbroken. Also he was carrying Neil with him, so it might've tough for him as a boy. DB might've got the news of Oberoi's & got heartbroken (but doesn't know that Shobana is related to this ).
Kabir might've got into accident that day. Neil & Kabir got admitted into same hospital where Vidhur took his wife at cesarean section for their baby. Operation might've happened but baby might be stillborn. Vidhur gets heartbroken because he lost his baby. Meanwhile, Neil gets attention of hospital staff for being alright even going through a accident. It's a miracle for them. Vidhur might've coincidentally got to know about that & using his power took Neil baby with him. Also informed his wife about it later. As they found Neil baby in this way, they might've thought to name him as Neil.
On the other hand Kabir gets saved but gets heartbroken about not getting information about his cousin brother. Years later, when he somehow got to know about his biological father, he started seeking revenge. Means, he is still trying to find about his cousin brother while trying to destroy Mahajans.
As he loved his mother, he uses her mother's maiden name which stands Kabir Oberoi.
CID
