My Sister Stole My Mate, And I Let Her

THE MISTAKE

SERAPHINA'S POV

"Seraphina!"

I jolted awake in bed, hearing my name from the urgency in my mother's voice on the phone. Her voice trembled through the phone, sharp and brittle.

"Mom?" My throat was raw. She hadn't reached out in ten years—not unless it was the worst kind of news.

"Your father—" Her breath hitched, then broke. "He's been attacked."

My stomach clenched. Ice-cold fear gripped me.

"What?!"

"Oh, Sera, he's barely clinging to life!" my mother sobbed brokenly.

I immediately threw the covers off me and jumped out of bed.

"Send me the hospital address," I said in a shaky voice. "I'll be there as soon as I can."

I tried not to make too much noise as I rushed down the stairs so I wouldn't wake my son, Daniel. The light underneath my husband, Kieran's, office told me he was still up. As Alpha of the pack, he always had too much to handle.

And if I were honest with myself—too much resentment toward me.

A decade-old mistake had bound us together. A mistake he'd never forgiven.

So, I didn't plan to bother him.

By the time I slid into the driver's seat, tears streaked down my face.

My father had always been invincible. Unshakable. The giant of my heart, even if he'd never wanted me as his daughter.

Even if he'd hated me. But I never imagined he could be taken from me like this—

I slammed my foot on the accelerator.

When I reached the hospital, my mother and brother sat like shadows outside the operating room. My chest tightened. Would the giant really fall?

I hesitated. I couldn't bring myself to step closer. Not when their disgust had exiled me long ago. After that night ten years ago, they'd erased me. To the world, they had only one daughter now—Celeste.

Should I even be here?

It had been ten years since we last spoke. Even after Daniel was born, all communication with the family had gone through Kieran. My father had made it clear—he never wanted to see my face again.

Would he really want to see me now?

What if he didn't? What if his resentment hadn't faded?

I hesitated, my pulse pounding in my ears—until the sharp swish of the operating room doors cut through my thoughts. The doctor walked out, pulling gloves off his fingers.

"Doctor!" I rushed forward before I could stop myself, my voice shaking. "How is my father?"

The grim expression on his face said it all. "I'm sorry. We did all we could... but his injuries were far too severe."

I pressed a hand to my mouth, choking back the sob clawing up my throat.

"Is he... gone?" Ethan, my brother, barely glanced at me before addressing the doctor, his voice rough.

"Not yet." The man shook his head slowly. "But he won't last the night. He's been asking for his daughter."

I took an instinctive step forward—then froze.

His daughter.

It couldn't be me. After ten years of indifference and resentment, the daughter my dying father wanted to see would never be me.

Ethan's laugh was ice. "Ten years, and our family is still paying for your mistakes!"

I turned to face him, tears streaking my cheeks. A decade since I'd last stood this close—since he'd looked at me. Time had sharpened him into a true Alpha: broader shoulders, harder jaw, a dominance that rolled off him in waves.

But the hatred in his eyes?

That hadn't changed.

My heart gave a vicious twist, like claws raking flesh.

"Because of you," he snarled at me, "Celeste moved away. Because of you, she can't be here. Because of you, Dad will die with his last wish unfulfilled."

"Yes, it's all my fault." My laugh was bitter, weighted with decades of pain. "After all these years, I'm still the first one blamed. No one cares about the truth—or how I feel!"

Tears burst forth, my outburst freezing Ethan for a heartbeat. But just as quickly, his voice turned razor-sharp:

"Your feelings? You stole your sister's fiancé and dare to talk about feelings?"

My nails dug deep into my palms, reopening that ugly old scar.

Ten years ago, at the Blood Moon Hunt, I'd just turned twenty—the age when every werewolf finds their mate. After a lifetime of being overlooked, I'd been desperate for that bond.

As a child, I'd foolishly dreamed it might be Kieran. But then he fell for Celeste—perfect, radiant Celeste, the darling of the entire Frostbane Pack—and I learned my place soon enough.

What was I? The Alpha's defective daughter, the one who couldn't even shift. Nothing.

When even my own family and pack barely spared me a glance, how could Kieran possibly want me? I never expected to change anything. But that night, when I heard about his impending engagement to Celeste, the pain cut deeper than any claw. For the first time, I let myself drown in drink.

I expected to wake up forgotten in some dark corner. Never did I imagine I'd find myself naked in Kieran's bed.

The liquor had burned through my senses. That night remained a haze of fractured memories. Before I could piece together what happened, Celeste burst in—her shriek slicing through the air as she took in the scene.

Then came the chaos: Celeste's hysterical sobs, Kieran's guilt-ridden apologies, the pack's venomous whispers, my stammered explanations—all silenced by my father's resounding slap across my face.

"I regret ever bringing you into this world!"

The aftermath played out in muted horror. Kieran carrying Celeste's unconscious form to the infirmary. Ethan snarling at gawking packmates. My mother's muffled weeping. And Father's eyes—Gods—that look of pure revulsion. I'd always known he despised me, but never with such intensity it stole the breath from my lungs.

"I didn't..." My whisper died unheard. No one listened. No one.

Overnight, I became the pack's favorite sin to punish. Where they'd once mocked my defective shifting, now they spat "whore" like a benediction. Even low-ranking Omegas cornered me in shadowed corridors, their hands and insults alike too bold. Females crossed themselves when I passed, hissing "husband-thief" like a curse.

The weight of it crushed me. When Celeste's admirers left death threats carved into my door, I gathered what little I owned and fled under a new moon. I intended to vanish forever... until the morning sickness began. Until the physician announced my pregnancy to the entire Blood Council.

That was the only reason Kieran married me. He was an honorable man, an Alpha who would never desert his heir.

Yet it tore my family apart.

My parents and brother hated me for breaking Celeste's heart. Kieran's pack, NightFang, loathed me because I was not the Luna they wanted. And Celeste was so enraged, she moved abroad.

"You ruined everything!" Ethan's accusing voice cut through my thoughts. The venom in his glare cut deep. Undiluted after a decade.

Blood may have made us siblings, but Ethan had never once treated me as his sister. Celeste was the only sister he cherished. He loathed me for driving her away.

But was it truly all my fault? I may be weak and ordinary, but never so vile as to deliberately seduce my sister's lover. Yet they never cared. They just needed someone to blame.

"See this?" My hands trembled, but my voice hardened like winter frost. "My voice was never heard. My existence never mattered. So tell me, Mom—" I turned to face her, throat constricted. "If you never wanted me, why didn't you just smother me in my cradle? Why pretend I still mattered enough to call me here?"

"How dare you speak to Mom like that?!" Ethan roared, his canines lengthening. "Marrying Kieran didn't magically make you Luna material. That title was always meant for Celeste!"

"I never asked for any of this!" I snarled back, bitterness filling my tone. "I was ready to disappear. You could have let Celeste and Kieran have their perfect mating ceremony and pretended I never existed!"

Ethan's lips curled mockingly. "Don't play the martyr," he sneered. "You knew damn well Kieran would never abandon his pup—"

"Ethan!" Mother's command carried the faintest echo of her former Luna authority, though her scent now held only exhaustion and grief. "Enough. We will not waste your father's final moments on this old blood feud."

She couldn't even look at me as she said, "Go see your father." Her gaze darted away like the sight of me pained her. Ethan shot me one last venomous glare before slumping into a chair.

Steeling myself, I pushed open the door.

The fear nearly choked me—fear of seeing that familiar disappointment in his eyes one last time. But when I saw him lying there, the man I'd spent my life both fearing and longing to please...

Gone was the towering figure of my nightmares. The father who'd once seemed invincible now lay motionless, his chest swathed in bandages, his face ashen. The eyes that had always burned with contempt when they looked at me... now held nothing at all.

Tears streamed down my face. Why did this hurt so much?

This man—this giant who'd hated me from the moment I presented as a wolfless. Who'd looked at Celeste with pride and me with shame.

The memory of our last meeting still clawed at my heart.

There had been no wedding for Kieran and me. No celebration. Only my father's iron grip forcing my hand to scrawl my name on the marriage paper.

"Now you've gotten what you wanted," he'd snarled, his Alpha power choking the air between us. "From this day forward, you are no daughter of mine."

I'd never wept so violently—never begged so desperately. But all I earned was the frozen line of his back and his final, venomous curse:

"Your birth was a mistake, Seraphina. Dare to show your face again, and I swear you'll never know another moment of happiness."

He kept his promise.

His curse had poisoned every moment of my life, while my "honorable" husband turned our marriage into a gilded cage with his endless silence and contempt.

I should have hated them all—this family, this fate.

But when my father's fingers twitched weakly on the sheets, my traitorous heart lurched. Before I could think, I was at his side, clutching his ice-cold hand.

"Dad?" My voice trembled with something dangerously close to hope.

His pale lips parted slightly, as if struggling to form words.

But before he could speak—

BEEEP—!

The heart monitor screamed. The line on the screen flattened.

"NO!" The cry tore from my throat. He couldn't leave—not like this. Not before I saw forgiveness in his eyes. Not before we could unravel the knots binding our hearts.

The door burst open. Ethan and Mother shoved me aside, sending me crashing to the floor.

"He's gone..." Mother collapsed against Ethan, her body wracked with violent sobs. "My mate... my Alpha...!"

Ethan's grief choked him silently—until his gaze locked onto me. His wolf was on the surface, teeth bared. I didn't doubt for a second he'd rip my throat out. Until Mother caught his arm.

"You viper," he hissed. "Whatever scrap of happiness you've clung to—I'll rip it from you."

A hollow laugh echoed through my mind. Why were they all so obsessed with stealing my happiness? Something I'd never had.

The doctor entered, murmuring to my mother, "Luna, we must prepare Alpha Edward's remains."

I numbly walked into the hall, my soul scraped raw, tears falling unchecked. As the pack's elite arrived, none acknowledged me—just as it had always been.

But their indifference barely influenced me now. I stood numb before the chamber holding Father's body, still unable to grasp the truth that he would never open his eyes to us again—

Until Kieran's voice cut through the silence.

"My deepest condolences, Margaret." He took my mother's hands, every inch the dutiful son-in-law. "Rest assured, I'll assist Ethan with every arrangement."

Moonlight from the windows gilded his broad shoulders, the silver streaks at his temples only heightening the aura of a prime Alpha in his prime. Not a hair out of place despite the midnight summons.

The deadliest Alpha of the NightFang Pack. Just his presence was enough to control the air.

"Your presence comforts me, Kieran," Mother wept, clutching his arm.

When he embraced her, those piercing amber eyes found mine over her shoulder—then flicked away as if spotting a stain on the wall.

"What exactly happened?" he asked as he turned to Ethan. "How could Edward get attacked?"

Ethan's jaw clenched. "Routine border patrol. But the bastard rogues came in numbers we've never seen—armed with silver weapons." His throat worked as he fought for control. "It was an ambush. Father never stood a chance."

My mother's renewed sobs filled the corridor. Kieran gripped Ethan's shoulder—

"The rogues will pay for this," he vowed.

I hovered at the periphery, an outsider in my own family's tragedy.

The three of them—Mother, Ethan, and Kieran—stood united in their grief, an unbreakable circle I couldn't penetrate.

"I've sent for Celeste," Ethan added suddenly. "She should be arriving soon."

"Oh, my poor girl!" Mother wept into her hands. "To miss her father's final moments..."

My gaze flickered unbidden to Kieran's face.

Our eyes locked again.

His expression remained unreadable—arctic, assessing, utterly devoid of warmth.

Ten years sharing a bed, yet he still felt galaxies away. I'd never touched his heart.

And now, with Celeste's return, a terrible truth crushed my chest like an iron weight: I was about to lose my second family.

If my wolf lived within me, she would have whined low in her throat. I didn't know if I could survive the coming storm—but one thing burned brighter than fear:

No matter what arrived, no one would take my son from me.

No one.