Harry turned the parchment over and looked at the back, hoping to see something else, but it was blank.

“Weekend after next,” whispered Hermione, who had read the note over Harry’s shoulder. “Here—take my quill and send this owl back straight away.”

Harry scribbled the dates down on the back of Sirius’s letter, tied it onto the brown owl’s leg, and watched it take flight again. What had he expected? Advice on how to survive underwater? He had been so intent on telling Sirius all about Snape and Moody he had completely forgotten to mention the egg’s clue.

“What’s he want to know about the next Hogsmeade weekend for?” said Ron.

“Dunno,” said Harry dully. The momentary happiness that had flared inside him at the sight of the owl had died. “Come on . . . Care of Magical Creatures.”

Whether Hagrid was trying to make up for the Blast-Ended Skrewts, or because there were now only two skrewts left, or because he was trying to prove he could do anything that Professor Grubbly-Plank could, Harry didn’t know, but Hagrid had been continuing her lessons on unicorns ever since he’d returned to work. It turned out that Hagrid knew quite as much about unicorns as he did about monsters, though it was clear that he found their lack of poisonous fangs disappointing.

Today he had managed to capture two unicorn foals. Unlike full-grown unicorns, they were pure gold. Parvati and Lavender went into transports of delight at the sight of them, and even Pansy Parkinson had to work hard to conceal how much she liked them.

“Easier ter spot than the adults,” Hagrid told the class. “They turn silver when they’re abou’ two years old, an’ they grow horns at aroun’ four. Don’ go pure white till they’re full grown, ’round about seven. They’re a bit more trustin’ when they’re babies . . . don’ mind boys so much . . . C’mon, move in a bit, yeh can pat ’em if yeh want . . . give ’em a few o’ these sugar lumps . . .

“You okay, Harry?” Hagrid muttered, moving aside slightly, while most of the others swarmed around the baby unicorns.

“Yeah,” said Harry.

“Jus’ nervous, eh?” said Hagrid.

“Bit,” said Harry.

“Harry,” said Hagrid, clapping a massive hand on his shoulder, so that Harry’s knees buckled under its weight, “I’d’ve bin worried before I saw yeh take on tha’ Horntail, but I know now yeh can do anythin’ yeh set yer mind ter. I’m not worried at all. Yeh’re goin’ ter be fine. Got yer clue worked out, haven’ yeh?”