Originally posted by: EkPaheli
Per this season’s canon we have no idea about whether or not Tanya was a mistress or not. Per S1, their marriage was not legal in a manner of speaking but only Nandini could sue them but she doesn’t.
Gautam would never be so crass as to taunt Karan over this, particularly because he knows Tulsi may not like it and Parth is an innocent regardless of his equation with Karan.
Per this season’s canon they may show Tanya was Karan’s first wife legally and Parth is hers via that marriage, meaning Parth is a legitimate child. Tanya has either been divorced by Karan once her connection with Ansh was out and Karan got the custody of their son or she died giving birth to him.
Poor Hiten because he’s gonna be called Dad by someone who looks so much older than him though they’re close to the same age. Not to mention that Rio may probably be shown like Ranvijay from Animal which means Karan is his Balbir 
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