According to original story"la juana..." by now Nikhil should have found out about Anu.In that story, Tulika does not know but Nikhil hears sunny call annanya as "ANU didi" and puts two and two togather. I don't know where this story is going...they have changed it a lot from the original plot. The original plot was more soft and romantic. Even while trying to read the translation, one could feel the under currents between the two main characters.