You have stated that your grandmother inherited a property of one of her sons (intestate succession is presumed here), along with his widow and daughter and later she settled her undivided share in favour of the other living son (your father). The settlement is perfectly valid in law.  Neither your father's sister nor the widow and the daughter of your father's deceased brother shall have any legal claim over the undivided share of your grandmother which she subsequently settled in your father's favour.

The same legal position holds good in respect of the other property too.

They do not have claim in property as once settlement deed is executed your father would be absolute owner of property 

- As per law after getting the share in the property , this will considered as the self acquired property of your grandmother , and by this way she  was having her right to transfer the same to any person , and none having right to claim over the same. 

- If the said settlement deed is registered from the office of the registrar , then your fathers sister or others having no right to claim over that property

Dear Client,

Please note that your grandmother would have the property as a self-acquired one, and hence, would have had the right to transfer the property.

In case the settlement deed had been registered at the Office of Registrar, your father would be considered as the absolute owner of such property.

Thank you.

If it's grandmother self acquired property then no. If ancestral than only her heirs like her children and grand children can claim

Father dies not need your consent 

he can execute registered gift deed in your brother favour 

The property is your father's absolute and exclusive one, and he can deal with it in any manner he deems fit. He may gift it to your brother or write a Will in his favour. Your consent is not at all necessary.

Hi, 

As it is a self-acquired property, there is no need for you to give consent when the property is being given to the brother. He can gift it to your brother as per his wishes.

Thank you. 

If your grandmother had transferred the share of property she inherited as her legitimate share out of her deceased son by a registered deed, then it cannot be challenged by her other legal heirs.

The above answer suits this question too.

If your father who acquired the said properties wanted to transfer the same to your brother, he can very well execute a registered settlement deed in his favor for which he need not obtain any consent or permission fro you or anyone. 

- Yes, without taking your consent , your father cannot give the property to your brother. 

Dear Sir,

It has become absolute property of your father which was acquired by him from his mother and she has given her absolute property thus no other person can claim such property or share in such property.