Want to get child custody but wife demanding more money

Dear Sir/Mam My spouse expired two years before due to theft (murder for gain) in my newly purchased house in the name of Wife with loan applied in my name from LIC for 20 years tenure. The thief arrested by the local police in the second day of the incident and the case is running separately. We have 4 months baby at the period of incident living together at home. At the time of this incident my parents-in-law get my child for temporary arrangement and after that i requested to get my baby from them but they didn't give instead of that they are demanding monthly payment and assets so decided to put case for child custody and this is running in counselling stage but i am not satisfied with my lawyer and counselling judges because they are approaching with partiality behaviour. My parents told that to drop this case and get stay order if any case will put from them in future. Please advice to proceed further.