1) Succession to the property of person married under this Act or customary marriage registered under this Act and that of their children, are governed by Indian Succession Act
2) where a Muslim contracts his marriage under the Special Marriage Act,
13. 1954, he ceases to be a Muslim for purposes of inheritance. Accordingly, after the death of such a Muslim his (or her) properties do not devolve under Muslim law of inheritance
3) on your husband demise you would be one of the legal heirs along with your children and mother in law
4) on your demise your property would devolve on your husband and children
5) your parents can bequeath only one third of property by will as per muslim personal law . hence entire property would not go to your brother