Property division between step brothers

Hi Sir/Ma'm

I want to ask is a step son is elegible/ can claim for the property self earned by his step mother.

We are 2 brothers and 1 sister, after the death of my elder brother's mother (first wife of my father), my father married again , and from 2nd wife i.e. my mother , we are 2 children me and my sister.

We have properties in 2 places ----

1) My Late Grand-Fathers property.

2) Property earned and made by My mother.

What would be the system of distribution in these cases legally?

As i know i would be getting the share in my Grand fathers property, but would we have to give the share to my brother from my mother's (step mother of my brother) property also?????

Plz reply ASAP.......

Thanks 

Devendra Mishra