Rights of father

Got married in dec'2014, wife gone to her parents home for ashadam month and also to see ailing grand father, earlier at my home we had fight on issue of me not conversing with her parents on phone and she asks for divorce but to wait till her sister marriage, after she left for her parents home, she gives the news of her pregnancy. Later,I conveyed her decision of divorce during our arguments to her father he takes it light and brushes aside as their daughter reacted on anger and she's a child. After ward when she called me on phone I talked normally and asked when she will come back and on whose permission she's staying with parents even after the purpose is over later her mom calls to my mom and complains that 1. am harassin her daughter on phone 2. I had beaten her during fight.3. (Once accidentally got a very very minor burn while I was ironing my shirt in our bedroom) I gave burns to her. As these were serious allegations on me my mom told to talk these matter face to face in front of few other people to make it clear where the wrong is and what is the truth. But, her parents never came for talks. Now she's still with her parents and delivered baby but this information is not shared to us. We are not in talking terms with them Please advise me. 1.On my rights for my child. .2. How can I take any action on them for not informing about birth of my child and how and when can I ask for divorce and on what grounds. Thanks in advance