The following is a song from Signing Time that the kids learned just last week. We recorded it at the end of the day, so their attention is definitely straying, but they are each so funny to watch (what with J's disappearing act, C's "dreams" coming out his ears, and N's bouncy-bouncing) that I just had to post it.
The lyrics go, "Lay down on your bed, pull your blankets high, turn out the lights, welcome the night. Dream, dream, sweet, dream." See if your child can still do the actions by following along with the video.