I just love the waltz, "Rocking the Babies to Sleep", key of D. I learned this at a workshop by Alan Jabbour, his source was Henry Reed's children. Let's play this at the 6:15 slow jam on April 2nd.
The tune appears in the Milliner-Koken Collection as "Rock All the Babies to Sleep"
Here's another source from folkmads.org: Rocking the Babies to Sleep Waltz