In Shashi Kumar Banerjee v. Subodh Kumar Banerjee, AIR 1964 SC 529, it was held as under:
“The mode of proving a Will does not ordinarily differ from that of proving any other document except as to the special requirement of attestation prescribed in the case of a Will by Section 63 of the Indian Succession Act. The onus of proving the will is on the propounder and in the absence of suspicious circumstances surrounding the execution of the Will, proof of testamentary capacity and the signature of the testator as required by law is sufficient to discharge the onus. Where however, there are suspicious circumstances, the onus is on the propounder to explain them to the satisfaction of the Court before the Court accepts the will as genuine. Where the caveator alleges undue influence, fraud and coercion, the onus is on him to prove the same. Even where there are no such pleas but the circumstances give rise to doubts, it is for the prpounder to satisfy the conscience of the Court. The suspicious circumstances may be as to the genuineness of the signature of the testator, the condition of the testator’s mind, the dispositions made in Will being unnatural, improbable or unfair in the light of relevant circumstances or there might be other indications in the Will to show that the testator’s mind was not free. In such a case the Court would naturally expect that all legitimate suspicion should be completely removed before the document is accepted as the last will of the testator. If the propounder himself takes part in the execution of the Will which confers a substantial benefit on him that is also a circumstance to be taken into account, and the propounder is required to remove the doubts by clear and satisfactory evidence. If the propounder succeeds in removing the suspicious circumstances, the Court would grant probate, even if the Will might be unnatural and might cut off wholly or in part near relations.
A will is executed to alter the ordinary mode of succession and by the very nature of things it is bound to result in either reducing or depriving the share of natural heir. If a person intends his property to pass to his natural heirs, there is no necessity at all of executing a Will. It is true that a propounder of the Will has to remove all suspicious circumstances. Suspicion means doubt, conjecture or mistrust. But the fact that the natural heirs have either been excluded or a lesser share has been given to them, by itself without anything more, cannot be held to be a suspicious circumstance especially in a case where the bequest has been made in favour of an offspring. As held in PPK Gopalan Nambiar v. PPK Balakrishnan Nambiar, AIR 1995 SC 1852, it is the duty of the propounder of the Will to remove all the suspected features, but there must be real, germane and valid suspicious features and not fantasy of the doubting mind. It has been held that if the propounder succeeds in removing the suspicious circumstance, the Court has to give effect to the Will, even if the Will might be unnantural in the sense that it has cut off wholly or in part, near relations. Smt. Veena Chawla v. Mahendra Singh, 2019 (136) ALR 332.