Exceptions to the rule of lapse
There is no lapse in either of the following cases:
1. Where the gift or disposition is made in discharge of a moral obligation recognised by the testator; or
2. Where the gift or disposition is in favour of any child or other issue of the testator, for any estate or interest not determinable at or before the death of the child or other issue and the child or other issue leaves issue surviving the testator.
In either case, the gift or disposition takes effect as if the deceased legatee had died immediately after the testator.
E.g. In his will, K left his house to his eldest son M. M pre-deceases his father, but leaves his children P an Q who are alive at the time of his father's (i.e. X's death). In his will, M leaves all of his estate to his wife Mrs. M. The fact that P and Q are alive at K's death keep in place the gift to M; the house passes to M's estate, and by means of M's will, passes to Mrs. M (Carefully contrast this position with the per stirpes rule in intestacy).