'Folder' in Metadata

I believe @Per Berntsen has the ccorrect answer, your sister's LrC has been customized so that Folder doesn't appear. You have to "un-customize" that part so that Folder does appear.

But on my sister's Lightroom, "Folder" is not an option for her under metadata

So, is your Sisters computer running MACOS or Windows?

Make sure that the Metadata panel is set to Default.

Click Customize at the bottom of the panel.

Check Folder  under Basic Info in the Customize dialog, then click Done.

If you click Arrange, you can change the order of the fields in the Metadata panel.

But on my sister's Lightroom, "Folder" is not an option for her under metadata. Is there a way to get it in there? I have version 12.5; she has version 13.1. Does 13.1 not have this option? If so I don't think I'll want to upgrade.

By @Solofaust

Nothing has changed in this regard between LrC 12 and 13. When comparing your system with your sister's, make sure that you are both using the same Metadata view in the Library module. Not all of the available views will include the "Folder" item (e.g. the "EXIF" view does not, but the "EXIF and IPTC" view does).

Not sure of what you are talking about. Please post in a reply, screenshots as examples.

Oh, and on a Windows rig, MACOS rigs may have different names/words for various actions. So is your Sisters computer also MACOS? Following are in LrC v13.1 on a Windows 11 rig:

First up, by clicking on Metadata

Second up, by clicking on Photo

 That would not be the only menu item difference between LrC on MACOS vs WINOS.

AND, are you sure what yo are mentioning is from the Menu bar, in Library Module, from the Metadata tab? As opposed to a right click on an image.