The Cyber Hymnal gives Sarah Doudney as the writer of the words and Ira David Sankey as the writer of the tune of 'The Christian's Goodnight'. I noted from a thread - quite some time ago now - that you have the Yazoo set 'How Can I Keep from Singing'. On volume 1, there is a 1928 recording of Memphis gospel/blues singer Lonnie McIntorsh 'Sleep, mother, sleep'. Its first verse goes:
Sleep on, mother, sleep on, lie down and take your rest
You've got to lay your head upon your Saviour's breast
I love you lord my saviour and my God
Sleep on, sleep on, sleep on
The first verse of the Doudney/Sankey hymn is:
Sleep on, belovèd, sleep, and take thy rest
Lay down thy head upon the Savior's breast
We love thee well, but Jesus loves thee best
Good night! Good night! Good night!
Fascinating spread of versions from Bristol, the Bahamas and Memphis.