"I think this is a bit much, Lily."

"Of course not! You look beautiful."

"You're as bad as Sirius. You two never tell me when I look bad."

"Because you never do," Lily rolled her eyes and stuffed her feet into the teetering heels that Sierra was sure only the redhead could pull off. Glancing at herself in the mirror, Sierra tried to see what her friend saw, but couldn't. The dress was made of velvet and a deep green colour, which accentuated Sierra's complexion but the skilful makeup Lily had done prevented her from looking too pale. Her right arm was encased in fabric while her left arm was left bare. Lily had looked like she wanted to argue when Sierra had picked up the dress, since it was worlds away from what she usually wore, but it had looked so perfect that she had been unable to find fault with it. The dress stopped a little below her knees, hiding her bulky cast when she stood up but ultimately showing it whenever she sat down. However, Sierra had refused to wear a floor-length dress, too afraid of tripping over the hem. She wore a pair of strappy sandals on her feet with just the slightest heel, knowing she could rely on one of the Marauders to lean on in case she got too tired. All in all, she supposed she could look worse.

"Wow," the slightly breathless voice from the doorway made Sierra giggle. James was staring at both girls with his jaw practically touching the floor. Sierra was sure his expression was more due to Lily's metallic silver cocktail dress with matching heels, but she smiled anyway and sat back down, watching James fawn over Lily and Lily try to look like his attention didn't make her want to smile.

"Aren't they cute?" Sirius' smooth voice made her jump, and she glanced back at him in surprise, not having heard him come in. His plain black suit was perfectly tailored, of course, though Sierra couldn't help but raise her eyebrows when she saw that his tie was the same colour as her dress.

"Lily filled you in?" she asked.

Sirius offered her a hand, helping her up from the chair and following the other couple out of the room. "Yeah, she did," his lips twitched. "Too much?"

"Its cute," Sierra pressed a quick kiss to his cheek and squeezed his hand. "Though I'm surprised you were okay with wearing green."

Sirius wrinkled his nose. "The things I do for you, eh?"

Sierra smiled. "You won't let me fall tonight, right?"

"Nah, the only falling you'll be doing is into bed with me."

"That will be hard, since you'll be on the floor."

"We can share the floor."

"In your dreams, Black."

"We do a lot more than share a floor in my dreams," Sirius waggled his eyebrows suggestively and Sierra resisted the urge to snort. She pinched his arm with her free hand and grasped the railing as they descended the stairs, surprised to find her descent almost painless. Downstairs, the knowing smile on Remus' face made her smile. Of course, they would have used an Anti-Trip charm.

"I take it you've been practicing your charms on the banisters?" asked Sierra once they were standing side-by-side.

"And the walls," Remus ran a hand through his hair. "Padfoot is unbearable when he's paranoid."

"Aren't you two the sweetest?" Sierra slipped her free arm through Remus' and ignored the exaggerated look of annoyance that Sirius threw her way. She stuck out her tongue. "Shut up, he didn't bring a date so you'll have to share me," she admonished.

Sirius genuinely looked horrified at the thought, causing Remus to chuckle. Sierra threw him a wink and allowed both boys to escort her into the ballroom.

The Potters' Christmas party was always a large affair, since both of them worked at the Ministry and had an abundance of family and friends outside of work as well. Sierra's father usually never failed to attend, but a quick glance around told Sierra that he was either late or not coming this year. The two matching whirlwinds in pink, however, assured her that her two cousins were in attendance and being supervised by a house-elf.

Remus excused himself after a few moments, saying he saw someone he knew, but Sierra suspected he wanted to avoid being a third wheel. She was about to insist he stay, but Sirius' tight hand on her arm told her to stay quiet. She waited until their friend was gone before speaking. "That was mean. You know he's here alone."

"He's not," Sirius rolled his eyes and jerked his head towards Remus' departing form. He was heading towards a group of people, at the centre of which was a pretty blonde girl who was smiling at him. "He went to the Halloween thing with her as well, remember? Lucy Bones."

"Bones?" Sierra frowned. "That name sounds familiar."

"Her brother was a prefect when we were in first year."

"Makes sense," Sierra shrugged and accepted a flute of champagne from the trays that were hovering in mid-air at regular intervals. "I didn't know they were dating."

Sirius snorted. "Mooney doesn't date. She's nice though."

"Does he not date because you've slept with every girl in Hogwarts and beyond?" asked Sierra with a raised eyebrow. Sirius looked uncomfortable and she choked back a laugh, patting his arm reassuringly. "Relax, I'm not going to freak out on you just because you're a bit of a man-whore."

"Was," corrected Sirius, his lips twitching. His jaw was still tense.

"Was," agreed Sierra. She put her empty glass down onto one of the tables they had ended up standing next to and reached up on her toes to press a quick kiss to his cheek. "Did I hit a nerve?" she asked, her lips brushing against his skin.

Sirius' arm tightened around her waist. "I'll forgive you if you sleep on the floor with me."

Sierra laughed. "Keep dreaming."

"I plan to," Sirius winked.

"You two look cozy," commented James, suddenly appearing next to them. At his side, Lily rolled her eyes, but smiled at him fondly.

"We are dating, James," pointed out Sierra.

"Lets try and keep it that way for a long time, eh?" James smiled, his goofy expression causing Sierra to giggle despite herself. "Why aren't you two dancing?"

"Because I have a cast on my knee?"

"Its all in the leading," James waved away her protests and plucked her hand out of Sirius' grip, giving his best friend a look when he attempted to steal back his girlfriend. "Trade, Padfoot."

Sirius looked like he wanted to argue, but he smiled grudgingly at Lily anyway. Sierra laughed and allowed herself to be led away by James, though she did hesitate when they finally reached the dance floor. "James, I don't think –"

"Scardey-cat," teased James. He gripped her waist and easily swung her into the circle of dancers, barely letting her feet rest on the ground. "See?" he grinned. "All in the leading."

"You're carrying me through this dance," said Sierra dryly.

"Just like I've carried you through Transfiguration since we were eleven," said James smugly.

"And how I've carried you through every other subject?"

"Oi, I'm good at studying," defended James. "I just don't like it."

"Right," Sierra bit her lip to keep from laughing. "So, why did you drag me away from them? I know you love me and all, but what's up?"

James' normally twinkling eyes softened. "You really do know me, don't you?"

"We've known each other a long time," Sierra shrugged, and then narrowed her eyes at his expression. "Spill it, Potter. You didn't get Lily pregnant, did you?"

"What? No! Merlin, no!" James looked genuinely horrified at the thought. "She would have killed me by now."

"Not if I got to you first," joked Sierra. "Seriously, though, what's wrong? You can tell me. We go way back, I won't tell the other two," she jerked her head in the direction of their significant others, who were chatting and dancing a few feet away.

"Its actually about that," James sighed. "Have you told Sirius about… him?"

Sierra's eyes hardened. "James –"

"I haven't said a word," assured James quickly. "But," he sighed. "Sirius really cares about you, Sierra. Heck, I want to say he loves you but I'm scared you'll run away if I drop that bomb on you too soon. But he does care, and he notices things. Don't act like you don't know what I'm talking about," he added. "He told me how insecure you get. He's my best mate and he's overthinking every little thing he says and does to you, and that's something I've never seen him do. But I love you too," he squeezed her hand, coaxing her to raise her eyes from where she'd fixe them on the floor when he'd started talking. "You're my baby sister, and you deserve a bloke who can make you happy. Just tell him, Sissy," the childhood nickname that she hadn't heard him use in years made her smile slightly. "You'll feel better, I promise."

"I don't know if he'll understand."

"He'll understand as well as you explain it, Sierra. And if he reacts badly, I'll hex him."

Sierra snorted, the tension immediately leaving her. "You're ridiculous, James Potter."

"You love me," James winked. The song ended and he guided her back to Lily and Sirius, who were both smiling. "Trade back, Sirius?"

"You're the boss, Prongs," said Sirius dryly. He took Sierra's hand out of James' and turned his gaze to her, his eyes softening immediately. "You're not tired, are you?"

"I think I have it in me for one more dance," said Sierra, noting how her words made his smile widen. She instantly felt bad. "Sirius, if you're bored –"

"Don't complete that sentence," Sirius rolled his eyes and led her in another dance, this one slower. Sierra wrapped her arms around his neck and sighed, resting her head against his shoulder. She felt him kiss the top of her head. "I'm never bored when I'm with you. You're too mean."

"Someone's got to keep you on your toes, Black."

"Glad its you, Grayson."

She winked. "Wouldn't have it any other way."