Dear Arun,
Thank you for your query! I am Aadil and I will try to answer your question.
The short answer to your question is NO. The first will shall not be valid.
The laws regarding wills are contained in the Indian Succession Act of 1925, according to section 59 of which any person of sound mind may create a will pertaining to their property as long as they are aware of the consequences of their action, meaning a deaf, dumb, or blind person may also create a will if they know what they are doing.
Here, the first will was created with one of the sons as the legatee for an immovable property. Later on, another will was created on the same property with the legatee being the other son. Here, even if the first son was also mentioned in the second will as one of the legatees, it would be assumed that the will was created with the intention of canceling the first one since the property to be bequeathed are the same.
Section 70 of the Indian Succession Act pertains to the procedure for revoking an unprivileged will, wherein it is mentioned that the testator may revoke a will in the following ways:
By marriage;
By another will or codicil;
By some writing to declare their intention of revoking the said will which is executed in the same manner as an unprivileged will is required to be executed;
By burning, tearing, or otherwise destroying the will by the testator or by someone else in his presence and direction with the intention of revoking the same.
Here, it is evident that a will can be revoked by executing another will, and since the second will was created to bequeath the same property as in the first and although it does not explicitly mention the intention to revoke the first will, it is logical to assume that it was the intention of the testator to revoke the first will by creating a new will on the same property with a different legatee.
Therefore, since the second will is already canceled, it shall be assumed that both wills are canceled and therefore the person will be assumed to have died intestate.
I hope this helps. Thank you for your query!
Regards,
Aadil