code relative file path?

I have a source workbook which includes a button to open a new workbook from a template held in the same directory as the source workbook. In this new workbook is a button to autosave this new workbook into the child folder.

Is it possible to code the filepath as just the name of the child folder?

e.g.
Source workbook and template workbook in same folder.
When template workbook saved it will be saved into sub folder within the folder containing the source and template workbooks.

can you use "..\file name" to save in folder one level above source folder?