Title: What Lurks
Characters: Alec-centric, Isabelle, Maryse, Robert
Rating: PG-13 for language
Words: 1270
Summary: Alec can hear his parents fighting through the walls.
Notes: Written for the theme "panic attack," but didn't really turn out that way. No spoilers for the series, set pre-Jace and pre-Max.

Maryse's voice echoed down the stone corridors of the Institute, louder and angrier than her young son had ever heard it before. She spit curses every other word and called her husband vile things, screeching at him like he was the worst scum on earth. Alec closed the door to his bedroom with shaking hands, but the voices permeated the walls; he could hear his father's terse reply as though he'd been standing in the same room.

"Leave, then, if you're so goddamn unhappy!"

Alec's lip quivered and his heart began to beat wildly. He'd heard his parents fight before, but this— this was serious. There was no way Robert could have meant that. Robert loved Maryse more than anything in the world. Alec had heard him say so. Every time he went out on a hunt he would tell her he loved her— he loved her, and she loved him. Why couldn't they just stop fighting and realise that?

"Oh, you'd just love that, wouldn't you, Robert? You know perfectly well that I can't leave! The Clave would skin me alive! You are fucking stuck with me! I have responsibilities. I can't run away from all my problems like you!"

Alec pressed his hands over his ears and backed away from the door. His sweater— borrowed from Robert's closet ages ago and never given back— was ridiculously large on him; it hung down almost to his knobby knees and the sleeves fell comically past his fingertips. The fabric was soft against his ears as he clamped his hands over them, trying to drown out the yelling.

"You think I run away from my problems?" Robert spluttered, and even through so many layers of protection Alec could hear the accusation in his voice. "All I do is fight for you! Everything I do is for you, but it's never enough! Nothing's ever enough for you!"

Alec's chest was constricting and he stumbled backwards, tears stinging his eyes. He couldn't breathe, he couldn't think, he had to get away, why wouldn't they just stop...?

His back hit the door to his closet, and in a panic, Alec yanked the door open and practically dove into it, forcing himself as far into the corner of the cramped space as he could before pulling the door mostly shut on himself. It was dark in the closet, but the sounds from down the hall were softened by the piles of fabric and layers of drywall.

"I'm not enough for you? The moment things get tough at home you're gone, out the door, in someone else's bed! Don't think I don't know what you do when you're gone for days at a time—"

Alec drew his knees up to his chest and pulled his baggy sweater down over them, pulling it tight to hold him together while his world fell apart. It was warm and still smelled vaguely of Robert; the manly, musky scent that Alec associated with being strong and a hero. But his dad wasn't being a hero right now. The Shadowhunter was yelling vicious things at his wife, and Alec didn't understand why.

"Don't give me that bullshit Maryse, you don't know anything—"

Tears stung at Alec's eyes and his heart was racing so fast it almost hurt. He was hyperventilating, and even rocking softly back and forth wasn't calming his fraying nerves. Stop, just stop, please—

"You think I don't know? You think everyone doesn't know? Everyone knows, Robert! Even the Downworlders know! And I had to hear it from a goddamn bloodsucker that my own husband is sleeping around—"

The roar that Robert made in reply made Alec flinch with shock. The words he said fell on deaf ears, but the rage and humiliation in his voice made Alec shake almost violently. The floppy end of his too-long sleeve made its way into Alec's mouth and he began to chew on it like he hadn't since he was little. The other stayed firmly wrapped around his knees, as though he could make himself smaller than the tiny ball he was already curled in.

"...'Lec?" came a tiny squeak of a voice, and Alec stopped rocking for a moment, surprised he'd even heard it over the yelling. He let his wet sleeve fall from his mouth and used that hand to lightly shove at the closet door, opening it a few inches. Despite the racket his parents were still making, he could clearly make out the sound of his door closing and the soft patter of tiny feet crossing his bedroom.

Isabelle pulled open the closet door a fraction more before slipping inside, pulling it mostly shut behind her before she sat down carefully next to her big brother. Even in the gloom of the closet Alec could tell she'd been crying. Six years old and already braver than he, Isabelle was a force to be reckoned with, and it made his stomach clench painfully to see her cry.

"C'mere," Alec said quietly as he saw her shiver, wiping her hands furiously over her eyes. She was wearing only a thin cotton nightgown, and her feet were bare. He unwrapped his arm from around his knees and lifted it, allowing the smallest Lightwood to slide under it for warmth.

Isabelle tucked her toes between his legs and snuggled up against him, leaning her head on his chest. They were rarely this physically affectionate, but as the voices down the hall grew even louder, Alec doubted it mattered much. Alec put his sleeve back into his mouth and continued to gnaw on it, a nervous habit that he wouldn't break for years, despite no lack of trying from both parents. His other arm wrapped securely around his baby sister, his hand brushing away her long, dark hair to settle over her one exposed ear and block out the noise.

Something shattered— something made of glass, it sounded like— but Isabelle didn't even stir. Alec only jumped a little bit, and then looked down at her; she was fast asleep, one of her hands clenching the warm fabric of his sweater. Resentment stirred in his chest at the thought of Maryse and Robert keeping their daughter awake with their fight, scaring her like that.

Alec sighed and leaned his head on Isabelle's, swallowing hard past the lump in his throat even as the sounds of their parents' fighting stopped abruptly. He closed his eyes and held her a little closer, swearing then and there to never let anything hurt his baby sister— not even their parents. Never.

Maryse would find them like that in the morning after a brief, panicked search of their bedrooms, fast asleep and clutching each other, dried tear tracks on their cheeks. She would puff out her cheeks and lean against the doorway, watching her little angels with a soft smile even as guilt churned her stomach at the thought of what they must have overheard, how they must have felt. She would wake them up with little kisses on their foreheads and then sit them down on Alec's bed and tell them that she was sorry that they'd been woken by the fight. She's promise it wouldn't happen again (though she knew it probably would) and promise that she and Robert would reconcile. She'd tell them not to worry.

But until then Alec and Isabelle slept soundly, more soundly than either had slept in weeks, feeling safe and protected from the dangers they knew lurked out there in the real world— and, now, in their own home as well. But they had each other, and that, for them, was enough.