Muslim Ancestral Property Rights

Please indicate whether your grandmother is alive.

Also indicate whether your father has any brothers/sisters.

What is precisely stated in the WILL?

Yes, the critical issue is whether your grandmother is still alive

If  your grandmother is alive then your father cannot make a testamentary disposition of the property.

If your grandmother is not living then until she had made any arrangement to your father's name, your father cannot claim the title to the property, hence without  clear and marketable title your father cannot bequeath the property in any manner by a Will.

Have you seen the contents of the will yourself?  What was written in it?

You can revert with the details for more proper opinion.

As per Muslim personal law, a testator cannot bequeath more than one third of his property through a Will.