How to save a "duplicate" image

[wanderer]

Hi:
I have a burst of photos taken that I would like to keep.  One image in the set is flagged as a "duplicate" using the "visually identical, same file format" criteria.  They are not visually identical as the eyes and facial expression are slightly different.

How can I mark the "duplicate" as not a duplicate so that it isn't continually flagged when I add more photos to the database?

The photos are of a person, so understand they cannot be posted here.

[sybersitizen]

Maybe this: Open the built-in Duplicates category, select the files in question, right-click, and choose the Un-assign from current category function.