So it's great to hold your baby and rock your baby all day long. But why not give them the richness of that sensory environment for hours more at night as well? And I think that that's going to ...

When was 'Rock-a-Bye Baby' written? Like many lullabies, the exact origins of "Rock-a-Bye Baby" aren't entirely clear. The words – originally "hush-a-bye baby," not "rock-a-bye" – first ...