Fathers Propert

Dear Sir, My friend’s father bought an apartment in 2013 in his name with his hard earned money. He died intestate in the year 2015. He is left behind by two sons and wife. My friend’s mother rented out the apartment without his knowledge for Rs 8000/-, made an agreement on a white paper (just a white paper) with the tenants for 2 years and left to US to the other son who lives there. When my friend came to know about the incident, he went to the apartment and asked the tenants to vacate the apartment number of times. The tenants filed a police complaint against him claiming that his mother only rented the apartment. His mother wrote a letter to the local police commissioner, manager of my friends company against this episode requesting them to take suitable action against him. However nothing happened. Now my friend approached the local court and the tenant refused to turn up in the court and was set ex-parte. Now my questions are 1. Is the rental agreement valid? 2. Does my friend have any right to stay in the apartment? 3. His mother claims that he does not have any right to stay in the apartment as he was fed by them all these years and also because he is working he should stay outside. Is it valid? 4. My friend’s father bought him a car out of love when he was alive. Now His mother claims that since he was given a car he cannot stay in the apartment and that is the final settlement. 5. His mother blackmails him saying that she will pronounce that he has harassed & abused her for the past five years in the court. She mentioned the same thing in the letter written to the police commissioner. Will such a claim deprive him of his right in the property? 6. How long will it take in the court of law? 7. The tenants recently vacated the apartment and left. No one is staying in the apartment. Can my friend occupy the apartment when the case is pending before the court. Kindly explain in detail