What is the test for making a gift a class gift in a will?

Feeney, supra, Vol. 2 at p.156 provides the following commentary: It would seem that to make a gift a class gift the class members must have some common quality or characteristic. It would also seem that Kingsbury v. Walter is to be followed only when this is the case. In general, for there to be a class gift, the members of the group must bear a certain relationship to the testator or some other person, and differences in relationship may prevent the formation of a class. Though this is generally so, if the will or the surrounding circumstances show that the testator intended to create a class of persons bearing no particular relationship to him, or if related to him, related to him in different ways, the court should declare the gift to be a class gift.