Lullaby
Sirius could hear his brother crying. It was late at night so the house was silent, but even during the day, he could always hear since his brother’s room was right across the hallway. Regulus was crying for a good ten minutes by now and nobody came. That meant that he wasn’t hurt. Their parents had put charms around his crib, so they knew when he was hungry, needed to change, or well otherwise physically in need. Most likely Regulus was just sad or lonely or had a nightmare. He had these a lot lately. Their parents didn’t consider these as a reason that needed attention.
Still, the sound of his brother being sad was breaking Sirius’ heart. He quietly slipped from his own bed and pressed his ear to the door listening carefully if indeed no one is coming. He wasn’t supposed to be up at this hour let alone be out of his room.
The hallway seemed empty so reached out and turned the doorknob. To his left, there was this big staircase. Sirius hated it. The steps were still too big for him, and scary paintings were hanging over it. He turned his head focusing back on his goal. He tiptoed across the hallway and slipped into Regulus’ room.
His brother didn’t notice him at first too busy pressing the palms of his little hands to his face. Sirius was already well-practised in this. He pulled up a chair to the crib and climb on top of it. It was always hard to get in than get out.
“Reggie.” He softly called out to him. The small boy looked up startled but as soon as he saw his big brother he reach out making grabby hands at him.
“Siri.” He slurred his words. Apparently, Sirius was too complicated for him to pronounce so he got used to this nickname. Sirius always found him utterly adorable when he called him that.
“I know, I’m coming,” Sirius assured him and pulled himself up, and then flopped in the crib with practice. As soon as he got in Regulus was already crawling to him. He sat right beside his brother who pulled him in a tight hug caressing his fingers through the short curls.
“Did you have a nightmare?” Sirius whispered. His brother looked at him and nodded tears still streaming from his reddened eyes.
“I see. But don’t worry Reggie. I’m here and I’ll chase all the monsters away.” Regulus locked his tiny fists into Sirius's shirt and hid his face. Sirius wrapped his arms around him and started to cradle them. He could still feel how the tears were soaking his shirt but at least Regulus seemed to calm down by a bit.
“I’ll always come to you, little brother. Don’t worry. So how about I sing you something for a good night?” Sirius didn’t wait for an answer and started humming a soft melody he made up. He didn’t know any lullabies and didn’t want to sing any of the few songs their father played in his study. He made a mental note to learn some soon so he could do a better job as a big brother to his Reggie.