A diferença mais óbvia é que um é escrito em verso e o outro em prosa.
To Thangorodrim was the Thalion bome,
that mountain that meets the misty skies
on high over the hills that Hithlum sees
blackly brooding on the borders of the North.
There stretched on the stone of steepest peak
in bonds unbreakable they bound him living;
there the lord of woe in laughter stood,
there cursed him for ever and his kindred all
that should walk and wander in woe’s shadow
to a doom of death and dreadful end.
There the mighty man unmovéd sat,
but unveiled was his vision that he viewed afar
with eyes enchanted all earthly things,
and the weird of woe woven darkly
that fell on his folk— a fiend’s torment.
(The Lay of The Children of Hurin - Second Verison - Lines 233-247)
'You shall see and you shall confess that I do not lie,' said Morgoth. And taking Húrin back to Angband he set him in a chair of stone upon a high place of Thangorodrim, from which he could see afar the land of Hithlum in the west and the lands of Beleriand in the south. There he was bound by the power of Morgoth; and Morgoth standing beside him cursed him again and set his power upon him, so that he could not move from that place, nor die, until Morgoth should release him.
'Sit now there,' said Morgoth, 'and look out upon the lands where evil and despair shall come upon those whom you have delivered to me. For you have dared to mock me, and have questioned the power of Melkor, Master of the fates of Arda. Therefore with my eyes you shall see, and with my ears you shall hear, and nothing shall be hidden from you.'
The Children of Hurin - Chapter III
Existem outras diferenças também. A versão Lay é muito mais detalhada, usa uma versão anterior da história e é interrompida na metade do caminho.
These interrelated but independent stories had from far back stood out from the long and complex history of Valar, Elves and Men in Valinor and the Great Lands; and in the years that followed his abandonment of the Lost Tales before they were completed my father turned away from prose composition and began work on a long poem with the title Túrin son of Húrin and Glórund the Dragon, later changed in a revised version to The Children of Húrin. This was in the earlier 1920s, when he held appointments at the University of Leeds. For this poem he employed the ancient English alliterative metre (the verse form of Beowulf and other Anglo-Saxon poetry), imposing on modern English the demanding patterns of stress and 'initial rhyme' observed by the old poets: a skill in which he achieved great mastery, in very different modes, from the dramatic dialogue of The Homecoming of Bëorhtnoth to the elegy for the men who died in the battle of the Pelennor Fields. The alliterative Children of Húrin was by far the longest of his poems in this metre, running to well over two thousand lines; yet he conceived it on so lavish a scale that even so he had reached no further in the narrative than the assault of the Dragon on Nargothrond when he abandoned it. With so much more of the Lost Tale still to come it would have needed on this scale many more thousands of lines; while a second version, abandoned at an earlier point in the narrative, is about double the length of the first version to that same point.
The Children of Hurin - Appendix 1: The Evolution of the Great Tales
A versão publicada em The Children of Hurin combina a versão do texto que foi publicada em Unfinished Tales com as outras prosa versões do o texto e usa um pouco de edição para garantir a consistência. Um relato mais detalhado pode ser encontrado no segundo apêndice de Os Filhos de Hurin , "A Composição do Texto".