Sharyn suggested "Down in Yon Forest"

One of my favourites too! Particularly the version sung by Bruce Cockburn on his fabulous CD simply titled "Christmas".

Here are the words:

http://cockburnproject.net/songs&music/diyf.html

... and of course, a variant on the same theme, "The Corpus Christi Carol" (although probably not sung at Yuletide), particularly the achingly sweet version by the late Jeff Buckley.

And just to get back to my favourite obsession, I think "Down in Yon Forest" has strong mythic parallels with the Robin Hood death ballad (Child 120):

http://hesternic.tripod.com/herobound.htm

And speaking of Bruce Cockburn, he's written a modern hymn called "The Cry of a Tiny Babe", which, in its first verse, deals with Joseph's jealous anger about Mary's pregnancy, as in the Cherry Tree Carol.

Cheers, Hester