That is an interesting point, Jeff, and welcome to the Downs.
Does the experience of the parents in re seeing the trees mean that their children somehow gain the 'light', so to speak. I'm really not sure.
As for Gil-Galad, I reckon he was certainly not as powerful as Fingolfin, though very powerful all the same! Fingolfin wounded, though was not able to kill, Melkor - in fact, he was killed by Melkor. Gil-Galad, on the other hand, slew Sauron with Elendil - at the cost of their own lives (at least, this is my reading of Tolkien - I know Isildur has devoted followers ready to ascribe him credit in this matter
)
But the hereditary passing of the light of the trees? Anyone?