A little translation help..

[Galin]

Eruhin is actually attested in Quendi And Eldar, where Eruhíni 'Children of Eru' is explained as a translation of a Valarin expression. The explanation goes on to say...

'Besides the form -hin, -híni only used in composition after a parental name, Q has hína 'child', and hina only used in the vocative addressing a (young) child, especially in hinya (< hinanya) 'my child'. S. has hên, pl. hîn, mostly used as a prefix in patronymics or metronymics: as Hîn Húrin 'The Children of Húrin.'

JRRT, Quendi And Eldar, The War of the Jewels

And according to Words, Phrases And Passages:

KHIN-, child, only plural hīn(i)

[deleted: hindo, hinde...]

So in general we have to wonder sometimes with respect to Tolkien changing his mind, and also there are matters like usage and idiom to consider.