1. Mutation has nothing to do with the title of the property. The aw of inheritance operates without effected by the fact of mutation or none of it.

2. In other words all of you are co sharers of the property and have their respective due shares by succession and the nationality of the co sharers have nothing to do with this as well.

3. Since the property is joint then to sell it consent and signature of all the co sharers is required which can be done either by their physical presence or through their constituted attorney on the basis of POA.

4. If there is dispute as regards respective shares or lack of unanimity in selling the properties then make a mutual deed of partition.

If partition deed is not possible then only option left is to file a suit for partition.

1. Yes they are owner but the property need to be mutated as per the succession rules.

2. See all the successors name has to be added and they have to sign the sale deed. 

3. He can send a POA for his share for others share you need there POA or sign in sale deed.

Any Non Resident Indian (NRI), Person of Indian origin (PIO) or even a foreign national of non-Indian origin can inherit and hold property in India but required succession certificate. 

NRIs can either get the required Power of
Attorney document prepared in India or
abroad. However, POA sent to India from
abroad regarding property matters must be
signed and attested at the Indian Consulate.
Once the Indian Consulate attests the POA it
should be acceptable by registrars in India.

Need succesion certificate to sell the same. If all are agreed they can execute partition deed between them. Grand uncle can execute registered relinquishment deed. 

1) PIO have inherited the property 

2) you have  to apply for mutation of property in name of legal heirs 

3) grand uncle can execute POA in your favour to sell the property 

3) it should be attested before Indian consulate 

Surviving brother still holds the ownership and deceased brother share will inherit his heirs. He can give you POA to authorize you to sell the property or gift deed to trasfer his ownership to you. Both can execute at Indian embassy and than get re registered in India where property lies within 4 months.

For 3rd share, POA will be require from his legal heirs.

1. Succession certificate is not required for inheriting properties. the persons having OSI/PIO cards or their successors  will very much inherit their parental properties as per law.

2. N.A.

3. He can execute  a POA in favour of anybody in India including yourself and get his signature notarised before the appropriate officer of local Indian Consulate for sending the same to the POA holder in India for his registering gift or sale deed as decided by him.            

1.  The property can be inherited even without obtaining the mutation of the same to their names, the mutation records are mere formalities, whereas their possession and enjoyment shall be considered as practical because they are the legal heirs of their decesed father hence the properties left behind by their father shall automatically devolve on them equally.

2. Without an authorisation from their successors in interest you may not be able to sell the property.

3. He can execute a power of attorney deed in your favor after which you can sell the property on his behalf.

1. As per the information mentioned in the present query, makes it clear that you are the legal heir as per law of inheritance.
2. There would be equal shares for all including the children if any of those who has died now.
3. And when there are other shared also then you can’t sell without their permission or consent.
4. Yes, you need to apply for the succession certificate first wherein others would also be called.
5. Rest, need many more information so that can give precise advice.