generation gap

Immortal Thetis can't have aged a day
since Peleus first claimed her for his bed.
Her first-born's flesh had mouldered into clay,
before she would concede that he lay dead.
Mortality's a "gift" in Tolkien's eyes
to never weary of the tolling years.
A sacred thing, to love what has to die;
to season feasts of pleasure with hot tears.
The immortality Achilles won
was not the sort a mother'd hoped to share.
His glory glows as long as songs are sung,
but she prefers he'd left one heir, one Spare.
Fleet-footed sea-nymph brooding in her fjord
know all too much of mortals, and their wars.