1. Did your maternal grand father leave a will during his life time? If no will was made by him then his house fell in equal shares to your mother and her two sisters after the demise of your maternal grand father. She can give to you 5 acres without asking your bother as this is a property in which neither you nor your brother have any right until and unless expressly granted by your mother by way of a written instrument.

2. Your proprietary rights in the property of your father have no nexus with the property of your maternal grand father. So you can take your share.

your mother is absolute owner of 5 acres she inherited from her father . she can gift you 5 acres without your brother consent . she can also bequeath 5 cares to you by will .

2) you also have share in your father property . if your uncle is not willing to give a share file suit for partition .