Who is responsible for snatching Raghbir's love from him??

Well,looking at the recent promo,although it's clear that its someone from family, I do feel it could be work of Harshit and his wife because the former felt scared about Bani's possible presence and the later behaves rudely with Pragthi which explains her unsaid hatred for Raghbir too!!!!     And also, the way Raghbir calls Harshit "Bro" looks as if everything is not or may be was not always fine with them!!