Disclaimer: I own neither Buffy: The Vampire Slayer or Harry Potter. Just having a bit of fun!

A/N: This is a response the 'Parent Trap' challenge over at Twisting the Hellmouth. Ah, how I love an old cliche. I always seem to find myself in an HP mood come September, and since this is the first year I'm not going back to school myself, I actually have a bit of time to dust off some old bunnies (see what I did there?) and expand on them. I've got 7 chapters of this little darling written so far, which I'm guessing is about halfway, give or take, so expect semi-regular updates. I'm also kicking around ideas for a prequel, if things go over well. If you get the reference in the story title, kudos to you! If you don't, you haven't been watching good TV since Buffywent off the air.

So, without further ado...


Chapter One: Of Doomed Relationships

In which Harry and Buffy do not make up

"Damn it, Buffy, that nearly hit me!"

"Next time I won't miss!"

Harry scowled darkly. "Oh, for heaven's sake, would you just – "

"Don't you dare tell me to just calm down!"

"I was going to tell you to just shut up!"

"Fuck you, Harry!"

"Would it kill you to take a little responsibility for once in your life?" Harry demanded. "Stop acting like a bloody child and grow up!"

Buffy slapped him hard across the face. Harry stumbled back at the force of the blow, clutching his injured cheek. Droplets of blood welled up beneath his fingers where her nails had raked the skin.

"Don't you ever talk to me about responsibility," Buffy whispered, eyes flashing furiously. "You know nothing about my life."

"That," Harry said sharply, wiping the blood off his chin with his shirtsleeve, "is abundantly clear."

Buffy stared at him, her expression ice cold. "I'm leaving.

"Fine. Fine. Just…go."

Buffy turned on her heel and stalked down the short, cramped hallway of their rented apartment. The wails emanating from the bedroom only increased in volume as she drew nearer. She threw open the bedroom door, went directly to the closer of the two cribs, and scooped up the squalling infant. Clutching the baby close with one arm, she stuffed an extra blanket into a diaper bag and slung it over her shoulder.

Resolutely not looking at the second crib, Buffy turned to leave and found Harry blocking the doorway. His face was unreadable. They locked eyes, but he stayed silent and after a brief standstill she pushed past him into the hall. He didn't try to stop her, so she kept walking.

She paused only to shove her car keys into her purse and grab her jacket from the back of chair.

The door clicked gently shut behind her.

She made it to the parking lot before she broke down completely.

All of her energy suddenly left her, and she had to sit down until the dizzy feeling passed. She sank to the dirty pavement and leaned back against the wheel of her car, her purse and the diaper bag forgotten beside her.

I left, she thought numbly. It's over. Done. Finito.

The baby was still screaming, his cries bouncing back against the cars and asphalt. Hot tears prickled at the corners of her own eyes and she hugged him tightly to her chest. Something sharp twisted inside of her heart as she realized that she didn't even know which son she had left behind. Blinking fiercely, she checked now. There was a tiny 'S' embroidered on the corner of the blanket, so that meant it was William she had left with Harry.

"Will," she whispered into his brother's downy hair. "Oh, god, I left Will."

Quietly, she began to cry.

When the Slayer on duty didn't recognize her, Buffy knew she had stayed away too long. Adjusting the baby in her arms, Buffy sent the girl a veritable death glare.

"Get Giles," she hissed angrily, only the baby finally asleep in her arms stopping her from screaming.

"It's four o'clock in the morning," the girl argued stubbornly. "Mr. Giles is asleep and isn't to be disturbed."

Buffy nearly throttled her on the spot. "I don't care if he's asleep or having tea with Gandi, the Pope, and the Queen of England herself - wake him up! Tell him Buffy Summers is here to see him!"

"Buffy Summers is retired," the girl argued.

"Listen up, you little snot, if it weren't for me, you wouldn't even be a slayer. If you don't call Giles down here right now, I will break every bone in your body and then go and wake him up myself!

The girl was beginning to look unsure of herself, and Buffy noticed too late what had to be an alarm button next to the controls for the voice box, but before either of them could react, a third figure joined them at the gate.

"What the hell is going - B?" Faith fell back in surprise.

"Hi, Faith," Buffy said tiredly.

"B!" Faith repeated with a grin. She moved in as though to hug or punch her - Buffy could never tell which with Faith - but fell back again at the sight of the baby. Her gaze flickered back up to Buffy's face. "Buffy?"

"I need Giles," Buffy said, ashamed at the helplessness in her voice. "Please, I'll explain everything - just -"

"Got it." Faith nodded, understanding in her eyes. "Laura!" she barked, turning to the younger slayer. "Wake up Mr. Giles and tell him to meet us in the kitchen."

Laura hesitated.

"Now," Faith growled. The girl ran.

Buffy smiled in spite of herself. "Look at you, all General Faith."

They began making their way up to the manor house at a more sedate pace.

Faith shrugged. "Someone had to take the position after you left. Don't worry: we'll have you striking fear into their little slayer hearts before the week's out." She grinned, teeth flashing bright in the dark.

"Ugh," Buffy said.

Faith laughed suddenly, loud and bright. "The Chosen Two, together again! Plus one, of course," she amended, glancing at the baby in Buffy's arm. "His dad?"

"Gone," Buffy said shortly.

"Bastard," Faith proclaimed, with conviction.

Buffy didn't bother correcting her.

By the time Harry made it to Ottery St. Catchpole, it was close to dinner time because apparating babies across oceans was frowned upon, and floo travel only slightly less so, so in the end he'd had to get a portkey made up at the American Bureau. It dumped him a mile and a half from his intended destination, so he had to take a muggle cab the rest of the way.

By the time he reached the Burrow, Harry was really beginning to wish that he hadn't, or at the very least had thought out what he was going to say because he couldn't very well walk into Mrs. Weasley's kitchen with a baby unannounced. Only, he couldn't stay standing in the middle of the lane, either, and Will was probably getting hungry, and Harry knew that if he didn't act soon, he would lose his nerve entirely.

When the front door opened and Arthur Weasley stuck his head out curiously, Harry knew he had misjudged his timing, because the clink of silverware and the aroma of good cooking drifted out around him and from the sound of the raucous laughter, a family dinner was in full swing.

"Harry!" Arthur exclaimed loudly, and even the conversation behind him wasn't enough to muffle it, because a sudden silence fell over the Burrow, preceding a great scraping of chairs as everyone rushed out to see for themselves.

For a moment, Harry thought he was about to get bowled over and curled himself around Will protectively, but Arthur stuck his arms out firmly and grabbed the doorframe, holding his large family back.

"Is that Harry? Where is he?"

"Get off my foot, let me see!"

"Harry, we were so worried!"

"Everybody move!"

Molly Weasley, the most forceful of the lot, squeezed to the very front of the crowd and peered out over her husband's shoulder. "Harry James Potter, where in Merlin's name have you been?!"

"Hi, Mrs. Weasley," Harry said tiredly, shifting Will gently as he began to wake up.

"What's that you're holding?" Molly squinted out into the gathering gloom. "Arthur, what's he holding?"

"It looks like a baby, dear," Arthur said calmly.

"A baby!"

Several people gasped loudly.

"Where did it come from?" Molly demanded. "Arthur, Harry's got a baby!"

"I can see that, Molls."

Harry shifted uncomfortably. "He's mine, Mrs. Weasley."

The group burst into frantic chatter once more. Will woke completely, and began to cry.

"Quiet!" Molly roared, spinning around, and began herding the family back inside, amid protests.

Arthur took Harry's elbow and guided him up the steps. "I think you'd best come inside, son."

Harry followed him into the kitchen, where the entire family had squashed inside to wait.

"Er, hello," he said belatedly, patting Will on the back. Everyone was there, it seemed. Hermione in particular looked like she was about to burst from wanting to speak, but the baby's cries held her back.

Molly bustled about, pouring warmed milk into a bottle. She took the baby before Harry could protest, and tucked him up in the crook of her elbow and popped the nipple of the bottle into his open mouth before he had time to notice the changing of hands. To Harry's amazement, Will quieted instantly, and began to suckle.

"There, now," Molly crooned, rocking back and forth ever so slightly. "That's much better. Oh, what a handsome little fellow you are!"

"The mother?" Arthur asked quietly.

Harry swallowed. "She left."

"The nerve!" Molly exclaimed. "What kind of mother abandons her child? Unfit!"

Harry was too tired to argue.