Oh crikey. Well, "gorffwys mewn tangnefedd" or "huno mewn hedd" (or even gorffwys mewn hedd or huno mewn tangnefedd) would be 'rest in peace'. To make things even more complicated, the old-fashioned Bible Welsh would spell it "gorphwys". As this is to be, literally, written in stone, you sure don't want a mistake, so I suggest she phones the Link Line at Welsh Language Board who will help.

Re: Gweddi dros Gymru, I can't think if I've ever seen it in English. I always use the Welsh version, of course. The only place I can think you might find it is in the Oxford Book of Welsh Verse in Translation (not sure if that's the proper title). Did you want a singable translation? There's an off chance that there might be a choral arrangement with an English translation; if so, try contacting the Welsh Music Information Centre via tycerdd.org.

I had friend who passed away a couple of years ago who used to visit Valentine on a weekly basis. Spent many an interesting hour ...

sian