Trease owned Hilltop in fee simple. By his will, he devised as follows: "Hilltop to such of my grandchildren who shall reach the age of 21; and by 55 this provision I intend to include all grandchildren whenever born." At the time of his death, Trease had three children and two grandchildren. Courts hold such a devise valid under the common law Rule Against Perpetuities. What is the best explanation of that determination?
All of Trease's children would be measuring lives. The rule of convenience closes the class of beneficiaries when any grandchild reaches the age of 21. There is a presumption that Trease intended to include only those grandchildren born prior to his death. There is a subsidiary rule of construction that dispositive instruments are to be interpreted so as to uphold interests rather than to invalidate them under the Rule Against Perpetuities