I awoke this morning to find Mabel Lou all scrunched up by the pillows, giving Baby Lou the vast majority of the bed. I have no idea what happened during the night, but it seems they had a falling out. And Baby clearly won!
UPDATE 1/29/14: The girls apparently made up last night! I awoke at three am to Mabel and Baby wrestling! There was much kissing and cuddling when it was all over!