I really like this poem called Spring and Fall by Gerard Manley Hopkins about a young girl's first sorrow for decay which anticipates sorrow for loss and death:

Márgarét, áre you gríeving
Over Goldengrove unleaving?
Leáves like the things of man, you
With your fresh thoughts care for, can you?
Ah! ás the heart grows older
It will come to such sights colder
By and by, nor spare a sigh
Though worlds of wanwood leafmeal lie;
And yet you wíll weep and know why.
Now no matter, child, the name:
Sórrow’s spríngs áre the same.
Nor mouth had, no nor mind, expressed
What heart heard of, ghost guessed:
It ís the blight man was born for,
It is Margaret you mourn for.