If you have a file (or a number of files) that are tagged but want to extend their tag to their entire families, here is how to do so. Let's use the tag 'From Zips' as an example:
Step 1. Go to the 'Tags' view and click on the '...' symbol against the already-assigned tag
Step 2. Select the 'Prompt' option then click on the 'Save' button
Step 3. In the 'Tags' view, click on the tag's name. This will list all of the files it is currently attached to in the 'Search' view as results
Step 4. Check the checkbox next to the search query, to select all the search results
Step 5. Click on the 'Tag' button in the right action panel
Step 6. Select the tag by clicking on it if it is one of the presented tags, or type its name into the search bar and click on it when it appears. Make sure the name of the tag is exactly the same as the one you want to spread to the files' families. If the 'Apply multiple tags' checkbox is enabled, click on the 'Apply' button after selecting the tag
Step 7. Select the 'Apply to entire family of each item' option and click on the 'Apply' button
The tag will be applied to the families of all files that are tagged. This may take a while if there are a lot of files to be tagged. Once this is complete, you can confirm that the tag has been spread to the files' families from the 'Tags' view by noting the difference in the number of files that the tag is assigned to (the number next to the tag's name)
NOTE: You may need to refresh the page for the number of tagged files to be updated.