This story was published for the first time here on DeviantArt as a submission for the Twinning Contest in the category "written entry that includes mental change".  It's 3,692 words.

A much longer version (9,766 words) appears under the title "Anniversary Present" in my new ebook short fiction collection, Unforgotten and Other Stories.  It continues past the point where this version ends and fleshes out the setting and characters more.  That collection also includes two other stories that are expanded from their original appearance and thirteen that have never appeared before online.