Every Father's Day in Maretime Bay, Sunny Starscout has a tradition that she likes to do. She sits down and all by herself she writes a letter: A letter to her father, Argyle.

This year, Sunny has lots of new developments to share with him. And it doesn't matter to her that he'll never be able to reply to any letters she sends.

(Spoilers!:Other tag is for a brief appearance by Zipp.)