Marion,

Again some remarks about the cradle song. Since it's Pennsylvania Dutch, I think we must recur to the Frankish dialects of the Rhine-Main area, viz. Palatine and Hessia. The os in schlof and schof must be pronounced long and closed, so one would prefer schloof and schoof.
The orthography used in the song shows that the writer knows High German; some letters are superflous for describing the sound.
Here the use of the -i ending for a diminutive sounds a little bit strange, instead a murmured indefinite short vowel is used (not unlike the Hebrew Shwa): so Bobbele, Dade, Mamme. Instead of Dade nowadays Babba (Papa) is preferred. But it also could be engl. Daddy. (Bobbele also is the local nickname for Boris Becker in his hometown.)
The article in the forms der and den, when not stressed in a deictic purpose, is reduced as much as possible to a de. In the 4th line the plural of "meadows" is used. High German: In den Wiesen, Frankish: In de Wisse<

Schlof, Bobbele, schlof!
De Daddy hiet die schof.
Die Mamma hiet die kleine Kieh,
In de Wisse, kiehl un grie.
Schlof, Bobbele, schlof.

Ebbie is on the right way with her translation, let me finish it:
Sleep, baby, sleep.
Daddy is tending the sheep.
Mommy is tending the little cows
in the meadows cool and green.
Sleep, baby, sleep.

Wilfried