Is a conditional gift in restraint of marriage valid?

Undoubtedly, the authorities establish the general rule that where there is a conditional gift in general restraint of marriage by which the testator seeks to cut down an interest which had given by the will the condition is void as against public policy: Morley v. Rennoldson (1843) 2 Hare 570, 12 L.J. Ch. 372. But, notwithstanding this general rule, the authorities seem to me clearly to hold that a condition in restraint of the second marriage, whether of a man or of a womanis not void,

In Allan v. Jackson (1874) 1 Ch. D. 399, 45 L.J. Ch. 310, the facts were that a testatrix gave the income of certain property to her niece (who was her adopted daughter) and her niece’s husband during their joint lives, and to the survivor during his or her life, with a proviso that if the husband survived his wife and married again the property should go over. The husband survived his wife and married again. It was held that the proviso was valid and that the gift over took effect.