CG37721 - Absolute entitlement: special cases: class closing rules: main rules
If a member’s share is to vest on birth and there are no members when the gift should vest, (for example a will leaves property `to my grandchildren’ and the testator has no grandchildren at this death) the class remains open until one can be sure that no more members can be born, which will be, subject to CG37730 - CG37731, the occasion of death of the testator’s last child. If on the other hand the testator has at least one grandchild, then the class consists of those grandchildren alive at his or her death.