Paternity Dispute: Who Wins?

A family law scenario is giving me sleepless nights: A 30-year-old man, Rohan, lives with his 28-year-old girlfriend, Nisha. They have a 2-year-old daughter, Ananya. Nisha claims Rohan is Ananya's biological father, but Rohan denies it, saying he and Nisha never had any romantic relation. Nisha's friends corroborate her story, saying Rohan was always around during those months. Rohan, on the other hand, has provided DNA evidence which shows he is not the biological father. Here's the question: Is Ananya's biological father legally entitled to claim custody, maintenance, and other rights if Nisha's allegations are proven to be true?

What do you guys think? Is Nisha's claim valid or is Rohan in the clear? Why?