According to Janaki Akka,this story of Sita being Ravan's daughter was neither there in the Valmiki Ramayan nor in the Ramcharitramanas by Tulsidas.I think that Neelkanthan selected this version because it portrayed Ravan in a more sympathetic light.Originally posted by: ElMystique
Neelkanthan portrayed Sita as Ravana's daughter.Was it considering Adhbuta Ramayana and story of Ghritasamvda ? What do you guys think about this theory?