1) your mother is absolute owner of the flat .

2) your mother as senior citizen is entitled to maintenance from her sons under provisions of maintenance of senior citizens act

3) your mother can move civil court and obtain an injunction restraining her son and daughter in law from entering her residential premises .

4) your mother can also file DV complaint against her son and daughter in law under Dv act and seek protection order / maintenance

5) your mother can also file police complaint against her son /daughter in law for criminal intimidation

6) you can engage a local lawyer from kolkata in this regard for filing DVcase / or moving civil court

It is advisable that you appoint a good lawyer for your mother who could help her claim maintenance from his sons or either file an eviction petition against your brother and his wife if they are troubling her to that extent.

Further, if you have not signed any document giving up your rights in the property then it is advisable that you dont do it until your brother takes good care of your mother. You mother being the senior citizen can also approach the police for such harrassment being meted out to her.

1. There are two aspects of your query. One is your broher's torture on your mother and another is your mother's maintenance since she is of old age,

2. To address the 1st problem, your mother can lodge a police complaint against your brother and obtain injunction on your brother and his family in entering into your mother's house. She can also file DV case against her son and daughter in law claiming protection and maintenance. This way the torturing problem will be taken care of,

3. she can also file suit as per maintenance of senior citizens act claiming maintenance from her son,

4. There is also an alternative for her maintenance since it may not be possible for her to approach the Court every time your brother fails to act to maintain her. She can very well sell of her house since it is in her name and sift to an old age home payment for which can be arranged from the interest to be generated from the sales proceeds to be received by her in selling her said house,

5. There are good numbers of old people who are settling for Old Age home in Kolkata rather than depending on their unwilling sons, for maintenance.

1. Your mother is the absolute owner of the flat, so she can exercise all the legal rights which the owner of a property can.

2. Your brother and his wife require the permission of your mother to reside in her house. To remedy the abuse which your mother has suffered at the hands of her son and daughter-in-law, she can file a lawsuit for eviction against them to evict them from her property. Pursuing this remedy will result in the eviction your brother and his wife from the property owned by your mother.

3. If your mother wishes to put an end to her misery without evicting her son and daughter-in-law from the house, then she may seek a restraint order from the court by filing domestic violence proceedings. If the restraint order is violated by your brother and his wife they can be imprisoned by the court.

4. Your mother can also claim financial support from your brother by filing a case for maintenance against him.

5. The legal process has to be set in motion by your mother alone. There is nothing you can do except to engage a lawyer for her.