Dear Rajni,
There are laws of inheritance of property in India. For Hindus, the Hindu Succession Act, 1956 (Amendment Act, 2005) and/or Indian Succession Act, 1925 apply. For Muslims and some others, the inheritance laws are a bit different.
Take note of the following (a bit in legal parlance):
Inheritance devolves around all Class I heirs (lineal descendants) if the property has been left intestate in equal proportions by law. Inheritance devolves around the beneficiary/executor (if the executor is a beneficiary) of the WILL if a WILL had been made. The last WILL and Codicil executed by the Testator are valid, legally. Either the WILL (registered or unregistered) is accepted by all heirs or is disputed. If disputed, the case will go up for Probate proceedings in the appropriate competent Court and the genuineness of the WILL be decided in Court. Once done, the Court will award a succession certificate/letter of administration or an award/decree, as the case may be.
As understood, the house property belongs to your sister's mother-in-law. It needs to be understood whether the mother-in-law inherited the property from her husband/father/mother by succession/relinquishing deed or is the original owner.
If she inherited it, was it a natural inheritance or by a WILL (testamentary succession) executed by its original owner (i.e. the Testator). Otherwise, her ownership itself may be under question by a competent Court of law. If her late husband's WILL is challenged/disputed by her sons, the competent Court will decide the ownership of the property.
If there is no WILL made by the original owner, then the mother-in-law and both her sons have an equal share of the property. If so, your sister can get her late husband's share. But if the property is undivided/not partitioned, then all owners can partition it for each's share mutually or go to Court to decide on its proper partition before anyone can sell his/her share.
Presuming that your mother-in-law is the sole/legal owner, she can either bequeath it to her sons (presuming there are no daughters or further sons) who are the Class 1 heirs by making a WILL in their favor. She can give it to only one child or several children in different/same proportions as she likes.
Alternatively, if she has not made a WILL she can make a WILL, a Living WILL or can even gift the property during her lifetime if she wishes so without any coercion or pressure from interested parties. If she is the rightful owner of the property, no one can claim their share until she passes away. Her WILL will only legally apply upon her demise.
If she does not make a WILL at all, then the property will go to both her sons (i.e. Class 1 heirs) in equal proportion by law. Since your sister's husband were two brothers, both will get an equal share or it will be decided by their mother through a WILL made by her. Since your sister's husband has passed away, the share of his property will be inherited by your sister in case of no WILL (i.e., intestate succession). She can sell her share if her share of the property is clearly partitionable.
Next, your sister's husband's farming land. The question is who did it originally belong to. If it was the husband's father, did he give it legally to both brothers or to your sister's husband. How was it given - in writing following the process of law or just verbally. Presuming that he was the legal owner, your sister and her children will own it now and can sell it at will.
In short, your sister can sell her share provided she has a clear title/ownership of her share of the property. The bigger question is whether her husband was the legal and rightful owner of his share of the property and the farming land. If yes, your sister will inherit your husband's share of the property and the land and can sell them.
Rahul
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