When it first appeared in Double Going the first line of “An Abiding” by Richard Foerster was the beginning of a long apostrophe to the stricken one.
The day the x-ray showed your lung ghost-laced
When the poem reappears in a slightly different incarnation in The Burning of Troy, all the lines remain the same, except for the keystone first line which switches the addressee
The day the x-ray showed his lung ghost-laced
What does not change from version to version is the “we” the reader is invited to identify with.
And so for day 1491