Originally posted by: misfit007
My theory is it will likely go one of two ways. 
Either Radhi won't tell her bio mother who she is, or she might be unable to. 
She might lose the locket and won't be able to prove who she is because she's also left all of her cards. 
Alternatively, she'll want to get to know her from a distance and judge her. The mom may eventually recognise who she is from the locket. Chances are there will be some misunderstanding first.
Aside from this, I can foresee the writers choosing two significant points of masala if they go down the predictable route. 
A - the mother telling her perfect family that she had a daughter out of wedlock and owning Radhi as hers. She might not, proving to be the imperfect mother for Radhi while being the perfect mother for her other daughters. 
I'm getting kind of PKYEK vibes, ironically also situated in Dehradun. 
B. One of the most significant conflicts for the mom will be choosing between her daughters, so some conflict or contradiction between the children seems likely. I can't see EK's writers letting go of such a vast conflict point. Given that it's an EK show, one of Radhi's half-sisters might fall for Rey in the future or be involved with him, creating more conflict. Or they may fall for a parallel lead who likes Radhi instead. 
I will be very, very surprised if the mother simply accepts her, and so does the family, giving her their name and identity. It would be so unlike a Balaji Production but so refreshing if it happens because it would give Radhi a strong backbone.