IT'S TIME TO SAY GOODNIGHT was recorded by the BBC Dance Orchestra, Al Bowlly, and Ray Noble. These lyrics come from a couple of sound samples of a much later recording by Connie Francis. I don't know whether they're complete. The publication data comes from the National Library of Australia web site. It sounds like a lullaby in waltz time:

IT'S TIME TO SAY GOODNIGHT
Words by Kate Gibson; music by Henry Hall; arranged by Jimmy Lally.
London: Ascherberg Hopwood & Crew, c1953.

It's time to say goodnight,
And it's time to close your eyes.
Let's put out the light,
Till the dawn breaks through the skies.
While long shadows creep,
May your dreams be sweet and bright.
In a moment, you'll be sound asleep.
It's time to say goodnight.


[By the way, as far as I can tell, IT'S TIME TO SAY GOODNIGHT was not used in the film version of "Dancing at Lughnasa" and does not appear in the soundtrack album.]