Please help me out

Can anyone PLS tell me what is the secret of Parth that his sister wanted to tell Jahnvi in earlier episodes? Moreover, Parth told Jahnvi if his parents has told everything abt him. When Parth's parents wanted 25 lakh, the relative of Jahnvi stopped them by blackmailing them with the threat that she would leak out everything.

What's the SECRET? Moreover, who was the guy locked up in PArth's house and was released by Jahnvi's father?

I don't think they've released the secret yet. If they have then it has to do with the greediness of Parth's parents.