Is NOC of siblings required in case of transfer of property through Will?

1. My father is living in our current house (property) since last 40+ years. His uncle (Mausi's husband) has created a Will in August 2016 and also registered the same at that time in which his uncle has mentioned that after his death, entire property should be transferred to his Wife's name (i.e. my father's Mausi) and after her death, that entire property should be transferred to my father's name. In that Will, name of no single person is mentioned other than my father's and his Mausi's names. My father's Mausi and her Husband had no issue (Son/Daughter). 2. In September 2016, my father's uncle (Mausi's husband) passed away and in October 2016, my father's Aunt (Mausi) passed away without making any new Will. 3. Now, if my father go to execute this Will and request our housing society officials for membership of the society, then they tell us that you must get NOC from the legal heirs of your Uncle (Mausi's husband). Without that NOC, we can not give you membership of the society even though you have a registered Will. So in this case do we really need to get NOC from the legal heirs of Mausi's husband or not needed?