Harry aged 5

The afternoon sun filtered through the tall windows of Grimmauld Place, casting bright shadows on the wall. Sirius sat in the study with Harry on his lap, guiding the five-year-old's finger along the sentences of a brightly coloured children's book. The room was filled with the scent of old parchment and the soft rustling of pages, blending into the background hum of a summer afternoon.

"See, Harry? Let's sound this word out," Sirius said, his voice warm and encouraging. He pointed Harry's finger at a word he knew would pique the child's interest.

"D-R-A-G-O-N," Harry spelled out slowly, his face lighting up with excitement. "Dragons like Charlie knows about!" he exclaimed, remembering the stories Ron's brother Charlie had told them about. Charlie knew everything there was to know about dragons, and one day he would be a dragon tamer!

Sirius chuckled, his eyes twinkling. "Exactly. Now let's try this sentence," he continued, pointing to the rest of the line.

Harry furrowed his brow in concentration, his small face serious as he carefully sounded out each word. "The…dragon…flew…above…the…clouds."

"Brilliant, Harry!" Sirius exclaimed, giving him an encouraging squeeze. "You're really getting the hang of this." Harry beamed with pride, his cheeks flushing with the warmth of his godfather's praise. They continued working through the pages, Harry's confidence growing with each successful sentence.

After a half-hour, Sirius sensed the boy was becoming restless. Harry's fingers started to fidget, and his gaze wandered to the sunlit window. Deciding to finish up their lesson, Sirius closed the book with a smile. "I think that's enough for today, pup. You did great."

Harry jumped up from the mans lap, heading up to his toy room and greeting the portraits in the corridor as he did. Sirius had taken down a few of the meaner portraits, so the remaining ones were those who either entertained or at the least put up with the small child. Harry continued past the playroom, moving further down the corridor to see if there were any portraits he might not have met yet.

Eventually, Harry stopped outside of a closed door. He hadn't really noticed the room before, or if he had, he hadn't been terribly interested. A plaque on the door had caught his eye, the slightly tarnished brass occasionally catching the sunlight from the window opposite.

"RAB," Harry sounded out slowly, recognising the letters on the plaque from his reading lessons. Sirius!" he called towards the drawing-room, his voice echoing down the hallway. "What does RAB mean?" he asked as Sirius emerged at the bottom of the staircase and began making his way upstairs.

Sirius approached the boy, swallowing tightly as his smile faded slightly. He reached out a hand, running his fingers over the slightly indented lettering, and allowing memories to drift to the surface. "That, Harry, stands for Regulus Arcturus Black. He was my brother."

Harry's eyes widened with curiosity and surprise. "Your brother? Can I meet him?"

Sirius' expression softened with a mixture of sadness and fondness. He knelt down to Harry's level, swallowing the lump that had started to form in his throat, though largely unsuccessfully. "I wish you could, Harry. But Regulus passed away a long time ago."

Harry's face fell, a shadow of disappointment crossing his features. "Passed away? What happened to him?"

Sirius sighed, searching for the right words to explain. He wanted to be honest, but he didn't want to scar the child any more than he already was. "Regulus…well he was very brave. He made a difficult choice to try and do something good, but it was dangerous, and he didn't make it. He died trying to do the right thing."

Harry looked at the door with a new sense of reverence, his small hand resting on the tarnished door. "So, he was a hero?"

Sirius nodded slowly, a small smile tugging at his lips despite the sorrow in his eyes. "Yes, Harry, in his own way, I suppose he was a hero."

"Can we go inside?" Harry asked, his curiosity piqued and his green eyes wide with wonder.

Sirius hesitated for a moment, the past mingling with the present in a rush of emotion. But then he nodded, "Alright, but it might be a bit dusty in there. We'll have to be careful."

Sirius gently pushed the door open, and they stepped into the room. The air inside was cool and still, as if time had stopped. The room was filled with old furniture covered in white sheets. Sirius hadn't entered the room since returning to Grimmauld Place, and he assumed Kreacher must have been responsible for the sheets. The walls were adorned with various Quidditch posters and family photographs that had faded slightly with time.

Harry walked around, his small hand reaching out to brush along the covered furniture. He lifted a corner of one sheet, revealing an old, well-worn desk underneath. "Did you and Regulus play here when you were kids?" he asked, his voice hushed as if not to disturb the memories.

Sirius smiled wistfully, the sight of the familiar room tugging at his heart. "Yes, we did. We used to pretend we were knights or explorers, much like you and Ron do."

Harry smiled at the thought, walking back over and hugging Sirius around the legs. "Do you miss him?"

"I do," Sirius nodded, reaching down and picking Harry up before settling the child on his hip. He kissed the boy's head softly, the action both comforting and bittersweet. "You remind me of him sometimes," he added, his voice thick with emotion.

Harry blinked up at Sirius in surprise, "I do?" he asked, a small smile forming on his lips.

"Sometimes when I tickle you right here," Sirius said, tickling the boy's armpit and making him squeal in amusement, "you sound just like he did," he added with a grin.

Harry's laughter echoed in the quiet room, a sound so full of life that it seemed to chase away the lingering shadows. He wrapped his arms around Sirius' neck, feeling safe and loved. "I like that," he said, his voice soft with contentment.

Sirius held him close, savouring the moment. "Me too, Harry. Me too."

They spent the rest of the afternoon exploring the room together. Harry discovered an old toy broomstick under the bed, its handle worn smooth from years of use. Sirius showed him a hidden compartment in the desk where Regulus used to keep his secret stash of chocolate frogs. They found a collection of old Quidditch magazines, and Sirius regaled Harry with stories of the matches they had attended as children.

"Uncle Sirius?" Harry's voice broke the silence, drawing him back to the present.

"Yes, Harry?"

"Do you think Regulus would have liked me?"

Sirius smiled, his eyes shining with unshed tears. "I think he would have loved you, Harry. Just like I do."

Harry beamed, his heart swelling with happiness. "I'm glad".