1. O the death of your husband all his properties gets equally divided between his mother and widow provided he has not left any children.
2.The dependence of his mother on income of pension or other son does not relinquish her right of inheritance.
3. So you can claim the terminal benefits of your husband but you are entitled to only half of the amount while the other half will go to your MIL.
4. So meet his office and bank who would guide you about the formalities.