If Kavya got pregnant with Aniruddh's child, why does she want Vanraj to be the father? What are her motives here? And why does no one mention about Aniruddh....Does he not deserve to know about becoming a father or play a role in the child's life?
Why did she leave Aniruddh and come back to a place where no one cared about her? It could either be that he refused to accept the child or he was abusive towards her. But there's no mention of it as yet. And it's not as if Vanar was too caring.
Now all of it would make a bit of sense if it was shown that she felt insecure (naturally) due to Vanar-Jhuli's open preference for Anupamaa and plotting to get her back while Kavya was in the house and married to Vanar. He had refused to have a child with her in the past. So she decided to get pregnant outside and consolidate her position, as she knew a child would give her the acceptance and she'd hide the parentage. A negative turn here wouldn't be that bad but she is crying and has become bechaari. If she didn't want to be with Aniruddh, she could have raised the child herself, why force it on Vanar and family.
The only plausible explanation now could be that she is playing an ever bigger game by manipulating Soorajpamaa to fight on her behalf as she knows they'll listen to her eventually and Kavya becomes the truthful one also with a kid. But senseless makers won't show anything as such. Rather the track may close abruptly when more pressing matters are brought to Sooraj's attention.