A postwar story about the twins. All the ideas used here come from details Rowling shared outside the books.
Ideas:
1. After Fred Weasley died, George grew closer to his friend Angelina Johnson, his Quidditch teammate and Fred's Yule Ball date. It is said they remained romantically involved until they graduated, after which their relationship is unknown. George later married her, and they had a son and a daughter. Their eldest son inherited the name of the late Fred: Fred Weasley II.
2. Rowling was once asked how George coped with losing Fred. She said, "George would probably never get over Fred's death." After Fred died, George could no longer cast the Patronus Charm, because every happy memory he had was connected to Fred. George would never be able to conjure a patronus since all happy memories he had always involved Fred.
3. After Fred died, every mirror in the world became the Mirror of Erised for George. To George Weasley, every piece of mirror becomes the Mirror of Erised after Fred's death. (I couldn't find the original interview with Rowling, but this idea is also widely circulated in the West.)
Thanks to @Harry Potter's Secret Stories for translating the details shared outside the books.
Theme:
The author is so gorgeous! ! QAQ!!