Unregistered property sale

Though the  daughters of your grandfather  had  interest in the proprty   left behind by your grandfather at the time of his death  ,the property might have alloted to the share of your grandmother alone  and was  subsequently  gifted  to your father  with the consent of your Aunts (fathers  sisters ) will amount to relingquishing interest in the property by them , the subsequent conduct of these sissters  also   confirms the relingquishemnet  in  favor of your  father , therefore these sisters  do not retain any interst  in the property , this is  aslo  confirmrd by passage of time,

that on death of your father  yourself the (son ) and the  widow of your father  get equal shares in the property  ,

you  and your mother  are  now absolute  owners of the property  and therefore  can  dealwith the property  as absolte owners 

After the death of GF all the legal heirs i.e., wife, sons and daughters are entittle to claim their share.  Your GM had no right to claim as absolute owner.  Is there any doucment that property was given to GM by your GF?  Eventhough if it is presumed that proper was transferred to GM  by your GF and she has gifted to your father then your father is the absolute owner of such property and no one claim share in that.

Respected sir, this property was gifted to my father by my grandmother and there was No Objection signed and submitted by all my three aunts in 1989, only then was the property mutated to my fathers name in the land registration office. He had taken mortgages as well which would not have been possible without clear title.

Do I understand this correctly that this mechanism makes my father and after his death my mother and me the rightful owners...

Respected Sir, Thank you for your responses. My aunts have also placed an affidavit in the municipal corportation stating that my mother has no interest in the property after forging her signature. We have met the zonal manager and put our objection to it. My aunts are now trying to get the possession of the house as it is vacant. What steps should i take to sell the property ? 

The documents we have in regards to the mentioned property are:

1. Original registry on my grandfathers name (original)

2. Sale deed on my grandfathers name (original)

3. Mutation certificate showing conveyance to my fathers name (original)

4. Mortgage deed registered on my fathers name (original)

5. Gift document (by grandmother) and no objection (all three aunts) in 1989 (is in the land registration office)

6. House construction plans blueprints showing my dad as the owner (original)

Your Grand Mother does not have absolute power to GIFT the said property to your father.

No objection is issued only for the mutation of the property in the name of your father. This mutation in the name of your father does not by itself deprive the  rights of your aunts. If they have relinquised their rights by REGISTERED RELEASE DEED then only your father gets absolute rights over the said property. Unregistered No objection certificate does not confer any rights, title and interest in the property in the name of your father.