Children learn more through watching their parents
Abhir inevitably got the worst upbringing through residing with abheenav and akshara. Earlier during the kasauli leap it was shown that abhir had vandalised the place where abhimanyu was staying. His parents didn't do the needful in setting him straight. It depicts how abhir had been spoiled by these two.
Abhir had always been a witness of his mother's opportunistic nature and his foster father abhinav's incompetency. We all can agree that akshara and abhinav weren't healthy minded individuals. Both were mentally perverted to the extent of doing paternity fraud , making their son suffer through forced poverty etc etc..
Abhir as a child was capable enough to 'use' and throw abhimanyu to get back to his parents.
Abhir saw how his father abhimanyu left his own mother manjari and ruhi for akshara. The same ruhi who considered abhimanyu as poppy (almost as a father figure). In a nutshell abhir's all parents were opportunistic and selfish people who left without thinking what will happen to the people who loved them. It's the same as what abhir is doing to kiara.
...They all are mere tools to get TRP.....All will turn horrible at any second 
But origin... Who cares? Real bheek mangne ka kaam toh Dr. Beerla ne kiya tha 
Ganesh Kartikeya
Shiv Shakti
Mannat Har Khushi Paane Ki
Kyunki Saas Bhi Kabhi Bahu Thi 2
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