Beibl Mam is lovely and hymnlike, and the air to Morfa Rhuddlan fits the solemnity of the occasion. And if anyone is singing, I've always liked Eli Jenkins' Prayer from Under Milk Wood, though it's not traditional. The last line is particularly apt for a memorial service.

Every morning when I wake
Dear Lord, a little prayer I make
O please do keep thy lovely eye
On all poor creatures born to die

And every evening at sundown
I ask a blessing on the town
For whether we last the night or no
I'm sure is always touch-and-go.

We are not wholly bad or good
Who live our lives under Milk Wood
And thou, I know, wilt be the first
To see our best side, not our worst

O let us see another day
Bless us all this night, I pray
And to the sun we all will bow
And say good-bye – but just for now

- Dylan Thomas