Widow's rights on father-in-law property

You have stated that deceased owner was Hindu and has not left any WILL and you may refer Hindu Succession Law and ClassI/II relations as per it:

Class I relations: Son/Daughter/Widow/Mother/Son/Daughter of a pre-deceased son (per-deceased means “already Dead”)/Son/Daughter of a pre-deceased Daughter/Widow of a pre-deceased son/Son/Daughter of a pre-deceased son of a pre-deceased son (3 levels)/Widow of a pre-deceased son of a predeceased son

Class II relations: Father/Brother/Sister/Son’s daughter’s son/daughter,/Daughter’s son’s son/daughter/Daughter’s daughter’s son/daughter/Sibling son/daughter/Father’s Parents/Brother’s widow/Father’s sibling/Mother’s parents/Mother’s sibling

1.      If mother of second Son (unmarried) is alive she shall succeed for whole share and if mother also not alive ClassII relations shall come into picture. If first Son (married and brother of this Unmarried son) is alive then he being sibling shall succeed to get share.

2.      The wife of this married son shall succeed to get share only if her husband (brother of unmarried son) is not alive.

3.      The widow shall succeed to get share of her deceased husband alongwith mother and children of deceased husband.

The second son can give his estate to properly adopted son. The adoption should ideally be registered.

Widow certainly has a right over the share that her deceased husband would have received.

1. After Second son's death, who has rights on his part? whether the children of first son or second son's wife?

Upon the intestate death of this second son, his surviving class I legal heirs will be entitled to acquire the property that devolves on his name or as his share from the inherited properties.  Here since he has no children, his wife being the lone surviving class I legal heir, his share of property will go to her as his legal heir.  The children of first son cannot stake any claim in such properties when the wife is alive.

2. Whether childless widow can ask her rights behalf of husband through court?

She can very well issue notice for partition and separate possession of her share in the properties, if not acceded to, she can approach court of law  for relief and remedy.

3. If second son adopt a child after his father's death, he can transfer his part to adopted child?

If a son was adopted properly as per law, the adopted son can have a share in the intestate property  along with the wife of the deceased out of the share of properties of the deceased son.  The adopted son will lose his rights over the properties from his original father.

Reply well analysed by Mr.Kalaiselvan

Regret by oversight though the second son as unmarried.

Mother/Wife are ClassI legal heir of married son, having no children. 

1.since your grandfather had died intestate his property will devolve a) grandmother (if alive) and his children (in your case  if grandmother is not alive you will get 1/2 share and the widow of your brother will get 1/2 share

2.she need not go to court to claim her share.she can mutate 1/2 share in her name

But if in this case the Widow dies and having no children. Will the property go back to the brother again or the Class II heirs (brothers, sisters of widow) can claim the property. Irrespective of the will she has written. 

But if in this case the Widow dies and having no children. Will the property go back to the brother again or the Class II heirs (brothers, sisters of widow) can claim the property. Irrespective of the will she has written.