Witness responsibility in fmily settlement deed

It is not necessary that the attesting witness to a document should know the contents of the document hence there's no illegality about it.

Thank you sir..

Regards

1.yes, they can do that if they have share in said property. 

2. Yes,it is valid. 

3.yes, they have a right to claim.

4.the only mistake they did is that they didn't read the contents of document before signing it as witnesses. 

Under Indian law, an attesting witness to a document, like a will or a sale deed, is not required to know the contents of the document; their primary role is to confirm the execution of the document, not to understand or verify its contents. 

The attesting witness's function is to ensure that the person signing the document (the executant) signs it in their presence, or acknowledges their signature, and that the witness also signs the document in the presence of the executant. 

It is legal duty of every person to read and know the contents of document which he is signing as witness because if some legal problems occur in future he will also in trouble. 

Family members' family settlement means, they do not have a property? Your query lack clarity in my view.

Attesting Witness(es) do verify signature of the executant of the subject document(s).

The witness(s) have no right, interest, claim or title in the subject property.

The facts, as posted, are less than convincing.

OK Mr. Venu.  Thanks for your comments.