Number 12 Grimmauld Place, in northwest London, had been very lively these past few days.
After The Burrow had been burned to ashes by the Death Eaters with Fiendfyre, the homeless Weasley family accepted Sirius Black's invitation and temporarily moved into the Black family's ancestral home. Once they confirmed that You-Know-Who had been driven off like that, the Order of the Phoenix also relaxed their vigilance somewhat and chose this place, which in theory still carried a few security risks. As insurance, the White Wizard Dumbledore, so he could personally protect Harry, had also temporarily chosen to live here.
Fortunately, after Kreacher could no longer provide service, the Black family had gotten a Handy Robot to serve as their housekeeper. Otherwise, Mrs. Weasley alone truly would have found it difficult to shoulder such heavy housework. Aside from that, only Harry, who had become skilled at chores, Ginny, and Tonks, who occasionally came to help, could share some of Mrs. Weasley's burden.
Accordingly, the birthday that was only a few days away was completely different from usual for Harry. This would probably be the liveliest one he had ever spent in his life.
After entering Hogwarts, and before his third year, he had almost always hidden away alone at Number 4 Privet Drive to celebrate his birthday by himself. The Dursleys would give him things like coat hooks and old socks as presents. Only after he later met Allen and Flag did he begin to have some normal children's birthday experiences. Then, after his third year, when he and Sirius recognized each other as godfather and godson, his birthdays were basically spent with his godfather. Though that had been much happier than when he was little, a situation like this year, with so many people gathered together, was still extremely rare.