Sirius's son

Occulmency

"Study what?" Said Harry blankly.

"Occlumency, Potter. The magical defense of the mind against external penetration. An obscure branch of magic, but a highly useful one."

"Why do we have to study it?" Asked Harry looking angry.

"Surely you can make the link Potter; if not no doubt your sister will explain it to you. You will receive lessons once a week, but you will not tell anybody what you are doing, least of all Dolores Umbridge. You understand?"

"Yes, who's going to be teaching us?" Rigel thought the answer was fairly obvious and resisted rolling his eyes with difficulty.

"I am." Harry paled.

"Why can't Dumbledore teach them? Why does it have to be you? Rigel is a natural occulmens himself. He could teach them." Hissed Sirius.

"I suppose because it is a headmaster's privilege to delegate less enjoyable tasks, I assure you I did not beg for the job and I doubt Umbridge will not notice three-fifth years practicing the mind arts Black. I will expect you both at six o'clock on Monday evening. If anybody asks, you are taking remedial Potions. Nobody who has seen you in my classes could deny you need them. You Miss Potter may inform people that you are receiving detention for refusing to speak in my class, other teachers will also be keeping you in detentions under that reason in order to keep you out of Umbridge's grasp, they will inform you of the protocol when you return to Hogwarts."

"Wait a moment." Said Sirius, standing up.

"I am in rather a hurry, Black. Unlike you, I do not have unlimited leisure time."

"I'll get to the point then," Sirius said. "If I hear you're using these Occlumency lessons to give Harry and Eliza a hard time, you'll have me to."

"How touching." Snape sneered. "But I'm sure you'll be reassured to know that Professor McGonagall has insisted she is present during the lessons. So please direct any concerns or questions you have to her."

Leaving the room to head upstairs, Rigel heard the start of an argument brewing in the room he had just left but he ignored it.

That night's meal should have been a cheerful one with Mr.Weasley back amongst them; Rigel could tell Sirius was trying to make it so, yet when his father was not forcing himself to laugh loudly at Fred and George's jokes or offering everyone more food, his face fell back into a moody, brooding expression.

"Dumbledore wants to stop you from having those dreams about Voldemort," said Hermione at once. "Well, you won't be sorry not to have them anymore, will you?"

"Extra lessons with Snape?" said Ron, sounding aghast. "I'd rather have the nightmares!"

They were to return to Hogwarts on the Knight Bus the following day, escorted once again by Tonks, and Remus, both of whom were eating breakfast in the kitchen when Harry, Ron, and Hermione arrived there the next morning. The adults seemed to have been midway through the whispered conversation when the door opened; all of them looked around hastily and fell silent.

After a hurried breakfast, they pulled on jackets and scarves against the chilly gray January morning. They were shunted out into the icy winter air, with Tonks (today heavily disguised as a tall, tweedy woman with iron-gray hair) chivvying him down the steps. The door of number twelve slammed shut behind them.

They followed Lupin down the front steps. As he reached the pavement, Rigel looked around. Number twelve was shrinking rapidly as those on either side of it stretched sideways, squeezing it out of sight; one blink later, it had gone.