A/N: So this is really the first time that I've actually written MAS since I'm used to just writing just MarcoAce (it's my favorite after all), but the lovely beans on the MAS server are really inspiring and this was just seemed like it would be more interesting from a poly point of view instead of just a couple (more angst potential). Anyways please leave a comment and let me know what you think!

Based on the prompt: Person A was separated from their biological child. Several years later, they start dating Person B, and are delighted by B's adopted child. What A doesn't realize is that B's child is the child that A was separated from in the first place.

Enjoy!

"Are you sure you don't need any help?"

Ace shifted his phone to his other ear as he adjusted his backpack strap on his arm. "Yeah I'm fine, Sabo. I don't have much." Just a backpack and a suitcase full of clothes- he had sold almost everything else five years ago.

"If you say so. I'm really glad you're coming home."

Ace closed his eyes and grit his teeth. He could practically see Sabo's gentle smile in his mind. 'Home? Yeah right.'

"Thanks, Sabo. Marco's coming to pick me up, right?"

"He's already waiting for you at the station."

Of course he was. Marco was always prepared and punctual. Skills Ace lacked. "Alright. See you soon."

"Have a safe trip!" Ace sighed after he hung up. He liked talking to Sabo, but right now it was just exhausting.

Ace was traveling again, something that he had gotten very used to, but this time he was here to stay. He hadn't returned to Raftel- home he supposed- ever since he left. The thought of having to face everyone made his stomach swim and his head pound, and he was already tired from the travel. They all supported his return with the entire Newgate family already planning a party, but none of them were more supportive than Marco and Sabo.

"Come live with us, Ace!" Sabo had suggested during their last call together. Maybe Ace shouldn't have mused his return to them. He should have known they would start helping as soon as he mentioned needing a job (despite his inheritance money, he wasn't some sort of lazy slob) and a place to stay.

"Are you sure? You're still adjusting with the kid and all."

"There's plenty of room," Marco said. "And besides you wouldn't be doing it for nothing. If you can help babysit while you're looking for work then we'll call it even."

Him? A babysitter? The idea was ridiculous. Why would he do it? He couldn't raise a kid- something he had come to terms with a long time ago- and besides. Living with such a lovey-dovey couple made his chest hurt.

Yet here he was, moving into 37773 Sunshine Street. Of course they would live on such a perfectly, perfect street with a perfectly, perfect address. They probably had a white-picket fence too.

"Now Arriving at East Bluevale Station."

He grabbed his suitcase, strolling up to the train doors as it slowed to a stop. No one else got up with him. East Bluevale wasn't a popular station. Too far from the center of the city. Too small, but Ace knew that if he arrived in Central, then he wouldn't have been able to stop the whole family from coming.

It was quiet as he stepped off save for the rumbling of the train and the low hum of the vending machines. Lonely. He was used to it. The parking lot was sparse as well, and even though Sabo had helpfully informed him that Marco was arriving in a new minivan (perfect for kids), it was easy enough to spot it with Marco standing in front.

"Ace!" Ace could practically see how Marco's mood changed with the way he smiled that familiar smile that Ace hadn't seen in so long.

He had hardly moved, but suddenly, Marco was running up to him. Warm arms enveloped his body, but Ace found himself unable to resist the embrace. Marco was too warm, always too warm, and so his hand left the handle of his suitcase to hug him back.

"Sabo and I missed you," Marco said, words a mere whisper. He pulled back, so Ace could finally see him up close. He hadn't changed much: same stubble, same pretty, droopy eyes.

"Well it's been a long time," Ace said. "I- uh- Well…. You better have all missed me!" He smiled trying to make this reunion more light-hearted. Reunions were supposed to be happy events, right?

Thankfully, it seemed to work. Marco patted his back, leading him towards the car. "Absolutely. Thatch and Haruta kept whining about how you never called enough- which they were right, you know."

"Yeah, yeah! But hey, now I have a bunch of interesting stories to tell everyone."

"If you say so, yoi," Marco said, clearly skeptic of Ace's words, but Ace didn't have the heart to defend his reasoning. "Just relax now, Mr. Adventurer-"

"Is that nickname really necessary?"

"-I can't wait for you to see the new house."

New house, new car, new kid. It seemed like everything was new, except Marco and Sabo. They were still the same, or maybe that's just what Ace wanted to believe.

The car was spacious. They only had one daughter for now, but Ace didn't doubt that the two of them wanted to grow their family. Maybe he was the first step to that. Maybe they felt like they needed to reign him in from running away from everyone.

Marco frowned at him before he could even buckle his seatbelt. "You don't want to sit in front with me?"

"I wouldn't want to impose." Shotgun was Sabo's seat just like in Marco's old SUV. It was couple thing supposedly. Ace would always sit in the back as he watched the two laugh and talk and lean over for the occasional kiss. He made sure never to interrupt them (third-wheeling like a pro, he called it).

But Marco opened the door and smiled for him, and as always, Ace couldn't resist. "I insist. We have a lot to chat up on, yoi."

Ace knew that he was just saying that to convince him. Marco knew that car rides made him sleepy. Head resting against the window, the same radio station on that they would always listen to together, Ace drifted off as his hometown passed around him.

He didn't stir until the car began to slow on Sunshine Street. He was right. Their beautiful two-story home was surrounded with a white-picket fence, and the image was completed with Sabo standing in front and their daughter peeking out from behind him.

Ace yawned, looking over to Marco in the driver's seat, who smiled at him.

"Welcome home, Ace."