For some reason there are two parent folders namped Photos. They're both pointng to the same parent directory in Mac Finder, but they do not have duplicate content. Some of the sub-folders are present in both, but not all. I tried merging them by moving the content of one to the other, but it wouldn't allow me, citing duplicate folder names. Any suggestions?
If they both exist in the Finder, then do the following (in Lightroom). Select the folder you do not want, make sure you have all stacks expanded and no active filter, and select all photos in that folder by pressing Cmd-A. Then drag and drop those photos on the other folder. This will move all the photos to that folder, and leave the first folder empty. You can then remove that folder by right-clicking on it.