Rightful owner after death of grand father is his children and wife so in case your grandmother has also expired and your father alone is there then as of now he is owner after his death you your mother and sister shall have equal right

Since your father is mentally not well he cannot make a will or gift of same.

on grand father demise your father would inherit his property

2) on father demise your mother , you and your sister would be the legal heirs

Dear Cleint,

Your father is absolute owner of house acquired by his father by inheritance.

And what do u mean by mentally unstable.

Dear Client,

All the family members i.e. mother sister and your father including you are the rightful owners to the property. In your grand fathers house your mother and sister will get sharee.

I would advise the following manner:

1. Your father is next in line to be the owner of the house (provided he has no brothers or sisters);

2. If your grandfather is alive you can request him to transfer the flat to your name vide a Gift Deed;

3. You can advise your grandfather to execute a will in your and your mother's favour;

4. You could also get an NOC from sister that she has no claim on the flat.

this is inherited property and according to the Hindu personal law your sister is also entitled for share in this property. But she cannot claim any share in the lifetime of her father. Your father is suffering from mental disability therefore your mother can execute a will on behalf of your father after getting leave/permission of the court.  she can exclude her daughter from the property by executive a will deed. After the execution of will deed, the daughter/your sister cannot make any claim in the property.

The rightful owner is the one who has a valid title document standing in his name.

If your grandfather is alive and it's his self acquired property he's the legal owner. If your grandfather has died without leaving a Will and property is not partitioned then you have share on property along with your father and sister each of you will get 1/3rd share in property of your grandfather. Your mother will not be entitled to a share till your father is alive.

So as discussed if it's ancestral property all of you constitute a joint family and property belongs to all of you jointly.

If it is the anscestral one then you but sister also might get something depending pup on few things which are not clear at your end in the present query.

If your grandfather is living then he will be the absolute owner of the house property where you live with your family members.

If your grandfather is not living, then this property shall devolve equally on all his legal heirs provided your grandfather is reported to have died intestate.

In that case your father is entitled to a legitimate share in the property.

If your father is medically proved that he is mentally challenged then you may apply for court guardian to take care of your father and his property.

After being appointed as court guardian, the guardian shall take care of the properties that belong to your mentally challenged father till his lifetime, after which the properties shall devolve equally on all his legal heirs.

Thus during the lifetime of your father, this property cannot belong to a third person, be it his children or wife or anyone.

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1. Typically the First owner shall be the Father (son of Grandfather). AFTER his demise, the property shall belong to the residual legal heirs of Father. IF Grandfather is alive, THEN the rightful owner is the Grandfather.

Keep Smiling .... Hemant Agarwal