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I know that through Earendil's line that exception was granted to him and his family. However, I wonder if it is possible for some of the other half-elves to be presented with that similar option.
Whilst through Imrazor and Mithrellas, their son Galador died as a mortal, nothing is known of Gilimith, their daughter.
Surely there must have been other examples or a slight possibility for other cases.