I’ve found this Christmas song a week or two late, but as I have not come across it before and it is the next song the Guitar Accompaniment Book I’ll have a look at it.
The text is by Johann C. von Schmidt and translated by Melanie Schute. It is set to IHR KINDERLEIN, KOMMET by Johann Schulz.
There are many variants but this is the text used by OCP. They sell the sheet music here.
1 O come, little children, O come, one and all,
O come to the manger in Bethlehem’s stall
And see what the Father in heaven above
Has sent to us all on this earth with his love.
2 O see in the manger, so meek and so mild,
O see in the sift light the heavenly child,
In swaddling clothes folded, his beauty more sweet,
Than angels, whose voices his lowly birth greet.
3 His bed, little children, a manger with hay;
His mother and Joseph in ecstasy pray,
The shepherds in wonder their glad worship bring,
While chorus of angels sweet Glorias sing.