Does Working lady (Govt Job) entitled to get alimony

Dear Sir , My sister has a Govenment Job and her husband is a doctor by profession . They have a son (9 year old) from this marriage . After 10 years of marriage , her husband has left the home due to quarral at home and after that he has filed a case in court for divorce which is pending in a court .they are living separately since last 4 years and their Son is living with my sister . As My sister do not want divorce , she has denied divorce in the reply to the court . My question is - 1) As they are living separately , How court would take this factor ? Would it go against us ? 2) We have not claimed maintenance till now , should we entitled to get this ? 3) What is the legal way to bring the husband back to home ? 4) in case we loose the case , should my sister entitled to get alimony ? How much ? She is earning 22000.00 per month . Your replay will be highly appreciated . Pls send the reply on my e-mail id - [deleted] , [deleted] Regards , Anil