Where a legacy is given if a specified uncertain event shall happen and no time is mentioned in the will for the occurrence of that event, the legacy cannot take effect, unless such event happens before the period when the fund bequeathed is payable or distributable.
Illustrations:
(i) A legacy is bequeathed to A, and, in case of his death, to B. If A survives the testator, the legacy to B does not take effect.
(ii) A legacy is bequeathed to A, and, in case of his death without children, to B. If A survives the testator or dies in his lifetime leaving a child, the legacy to B does not take effect.
(iii) A legacy is bequeathed to A when and if he attains the age of 18, and, in case of his death, to B. A attains the age of 18. The Legacy to B does not take effect.
(iv) A legacy is bequeathed to A for life, and, after his death to B, and, "in case of B's death without children," to C. The words "in case of B's death without children" are to be understood as meaning in case B dies without children during the lifetime of A.
(v) A legacy is bequeathed to A for life, and, after his death to B, and, "in case of B's death," to C. The words "in case of B's death" are to be considered as meaning "in case B dies in the lifetime of A".
Legal Commentary & Landmark Judgments: Section 124
Section 124 codifies the rule that where a bequest is contingent upon a specified uncertain event without any time mentioned, the legacy cannot take effect unless the event happens before the period of distribution arrives.
Under this section, the 'period of distribution' is normally the death of the testator (for immediate gifts), or the determination of a preceding life estate (for deferred gifts). For example, if a legacy is given to A, and 'in case of his death without children' to B, and no time is specified, B takes only if A dies without children before the testator dies. If A survives the testator, A takes an absolute interest, and the gift over to B fails completely.
Section 124 prevents titles from being clouded for generations. Drafters frequently write: 'I give my estate to my son, but if he dies without children, then to my brother'. Under Section 124, if the son survives the father, the son takes absolutely and can sell the land immediately; the brother gets nothing, even if the son dies childless 40 years later.