A/N: I can't stay away - LOL! I've had this idea for months and months now and it's finally forming itself into a story that won't leave me alone. So I lovingly dedicate it to all my faithful and loyal readers who want MORE of my IPS stories - without you guys, I doubt my IPS muses would still be churning them out.

This is a VERY AU story based on the quote from the episode 'Son of Mann' and the idea that Mary got together with Marshall instead of Mark in high school. There will be back and forth in the storytelling between the present and past and also Mary and Marshall are a bit younger in this universe, in their mid-30's. Enjoy the ride - it's going to be an angsty one.

Marshall: I wish I'd had you in high school.

Mary: High school me would have eaten high school you alive.

-'Son of Mann'

Present Day

"Ladies and Gentlemen, I have turned on the fasten seat belt sign as we begin our final descent to Albuquerque. Please stow your tray tables and return your seats to their upright positions, and turn off all electronic devices in preparation for landing."

Liam removed the ear buds and turned off his iPhone, nudging the girl dozing on his shoulder. She sighed and burrowed further into his neck. "Jules," he whispered, removing one of her ear buds, "Turn off your music – we're landing."

Julia opened sleepy eyes and smiled at her boyfriend. "Already?"

He snorted. "Seriously? You've been asleep since we left Atlanta."

She smothered a yawn as she sat up and turned off her iPod. "I don't know how you stayed awake. Sleeping for ten nights on a gym floor was not fun."

Liam shrugged. "I guess I had stuff on my mind."

Her dark eyes met his light ones. "Are you still thinking about her?"

He shrugged again and looked out the window as the plane dipped below the clouds. She leaned over his shoulder to whisper in his ear. "Maybe it wasn't her- you've never seen her in person, you know."

He turned his head to glare at her. "I think I'd know my own –" he swallowed the word, and glanced around the crowded cabin of the plane, but the rest of their classmates were oblivious to their conversation. "Dad has pictures of her everywhere, Jules."

"But those pictures are seventeen years old," she pointed out quietly.

"She doesn't look that different – just older. Besides, I have her eyes," Liam swallowed as he turned and stared out the window again. Julia rested her chin on his shoulder. Anyone who passed by would think she was peering out the window when in fact she was comforting him the best she could in front of all their chaperones.

"Did she recognize you?"

"Why would she? I'm sure she's forgotten all about the son she left behind seventeen years ago-"

"Liam-" Julia placed her hand on his back.

"Drop it, Jules. I don't want to talk about it – not here, not now, ok?"

"Okay – but, you are going to tell your Dad, right?"

Liam leaned his forehead against the tiny window, as he thought of telling his dad the news that he had seen his mom in NYC. What would he say? Would he even believe him?

"I don't know-"

"You have to!" she hissed, leaning closer. "He needs to know."

"What makes you think he doesn't already know?" Liam whipped his head around to glare at her. "He's a US Marshall for God's sake – I'm not so sure he hasn't known for years where she's been."

"That's crazy – surely if he'd known he would have tried to bring her back – for you if not for him."

Liam shrugged. "Maybe he did and she said no – I've always had the feeling that things between my folks are very complicated."

Julia bit her lip. "But he still loves her, right? I mean, he still wears his wedding ring and everything."

He nodded. "Yeah, Dad still loves her – I can't think why. She's the one who ran out on us."

"He's never told you why?"

Liam shook his head. "Just that one day I could ask her myself."

Julia gasped. "So he does know where she is!"

He nodded slowly. "I've always thought so – but I don't know what he's waiting for. I mean, if he knew she was in NYC, he could have told me so I was prepared to run into her. I was a complete idiot and just let her walk away!"

Julia squeezed his hand. "I'm sure he'll help you find her again – if that's what you want?" she raised her eyebrows in a question.

He squeezed her hand back as the wheels touched down and they were thrown forward in their seats from the impact. "I don't know, Jules. I just don't know."

"There he is! Will!"

Liam waved to Rosa and weaved through the last few people beyond security and leaned down to embrace the petite woman who was so much more than their housekeeper. She had practically raised him and he loved her like the mother he'd never had. He pulled back but she captured his face in her hands, planting a kiss on each cheek. "Oh, how we missed you, carino! I have no idea how your father and I are going to survive in the fall when you go off to college."

Liam smiled. "Where is Dad?"

Rosa shrugged. "Where do you think?"

"Work."

"He wanted to be here-"

Liam bit down his disappointment. He knew that it was rare to have the kind of relationship he and his dad had – most of his friends didn't understand it at all and he didn't know how to explain it to them. Maybe it was the fact that his dad was all he'd had growing up and even though Marshall's job had kept him away periodically, Liam always knew that he came first in his dad's life. That's why he was dreading telling him about seeing his mom in NYC – he knew it would cause his father pain and that was the last thing he wanted.

There had been many nights when he couldn't sleep and had crept to the kitchen for a glass of water, passing his dad's room on the way. There was always a light on and Liam would creep closer and peer inside to see his dad sitting on the side of the bed, cradling a picture of the three of them taken when he was just a newborn. His dad would sometimes be whispering to the picture, and sometimes not, but always there would be a tear or two on his face. When he found him like this the night before he left, Liam could stand it no longer. He pushed the door open and walked inside.

"I was wondering how long it would take before you came inside."

Liam's mouth fell open. "You knew I was out there?"

Marshall smiled. "I'm a US Marshal, son. I've heard you get up every night for years – but tonight's the first time you've come inside – why?"

"Because I can't stand it anymore!" Liam crossed to the side of the bed and whipped the picture out of his dad's hands. "Why do you continue to torment yourself night after night? Put this away, Dad! It hurts me to see you like this."

Marshall sighed. "I'm sorry – I wait until I think you're asleep before-"

"That's not the point! Dad, you've got to move on! I don't want to go off to Harvard in the fall knowing that you sit here and wallow in misery every night. She's gone! She's not coming back."

"You don't know that."

"It's been seventeen years – isn't that enough proof? Fuck, Dad-"

"Watch your mouth, William Mann. You're not too old for me to wash your mouth out."

"Sorry – I just – she can't be worth all this –"

Marshall's eyes flashed as he snatched the picture back. "Until you've loved and lost and heard her side of things, I don't think you're in any position to judge her. Good night."

"Dad-"

"Good night, Will."

Their parting at the airport the next morning had been strained and even though they had texted multiple times a day while he was gone, Liam hadn't realized how much he missed his dad and wanted him to be here until he wasn't. Rosa had continued talking while he was lost in his thoughts and he was startled when the baggage conveyor belts came into view.

"And I've made your favorite meal – I know you've got to be tired of eating out."

Liam smiled. "Actually, the parents cooked for us in the school kitchen most of the time – but it was nothing like your cooking, Rosa. You're going to have to send me care packages when I'm at Harvard."

"Don't give her ideas, Son."

"Dad!"

Liam threw himself into Marshall's arms and the two embraced tightly. He pulled back to look into his dad's face. "I'm sorry for-"

Marshall shook his head. "The fault is mine."

"No, Dad, I shouldn't have-"

"Are you two done?" Rosa broke in and they turned to see that she had retrieved Liam's bags while they were arguing. "Because I want to get our boy home."

Marshall clapped his son on the shoulder. "Sounds good to me."

Liam groaned as he pushed his empty plate away. "Rosa, you've outdone yourself. I couldn't eat another bite."

She pouted as she pulled something from the fridge. "Not even my cherry pie?"

Liam moaned as Marshall laughed. "Well, maybe just a sliver."

After huge wedges of cherry pie and vanilla ice cream, Rosa shooed the men out of her kitchen so she could clean up and go home. Marshall carried his after dinner coffee to his office and Liam trailed after him, wondering if he should spoil the peace that had once again descended between them.

"So, are you going to tell me what's on your mind?"

Liam's head snapped up and Marshall smiled. "How do you always know?"

"I'm your father."

"Come on, dad – there's got to be some clue, some tell I have because I've been very careful to act normal tonight-"

Marshall smiled sadly. "You've been rubbing the knuckle of your right index finger – your mother used to do that when she was nervous or scared or had something on her mind that she wanted to tell me and wasn't sure how to."

Liam looked down and started as he saw that his father was right. He stuffed his hands in his pockets as he dropped into a chair. "Yeah, well, your left eye twitches when you're lying," he shot back.

Marshall grinned. "I know – that's why I never play poker." The smile slipped as he tasted his coffee. "So, what's up?"

Liam shifted uncomfortably in his chair. "Maybe we should wait until tomorrow."

Marshall cocked his head. "Will saving the news for tomorrow change anything?"

Liam thought for a few seconds before shaking his head. "No – I just – I don't want to hurt you, Dad."

Marshall leaned back in his chair, exhaling slowly. "This is about your mother."

Liam nodded. "I saw her – in the city."

"You're sure it was her?"

Liam nodded.

For several moments, Marshall didn't speak as he fiddled with the wedding band on his ring finger. Liam was dying to ask him a million questions but the pained faraway expression kept him quiet. Finally, Marshall focused back on his son. "Tell me what happened – don't leave anything out."

Liam cleared his throat. "We were leaving IHOP – it was yesterday morning – I texted you and sent you a couple of pics from the restaurant, remember?" he waited for his dad's nod before continuing. "Anyway, when I got back on the bus, I realized I'd left my phone on the table, so I told Mr. Lewinski and ran back inside. I was checking my phone for texts and not looking where I was going when I ran straight into her-" he paused to clear his throat again. "I opened my mouth to say sorry but when I saw it was her I couldn't speak. She apologized and asked me if I was OK. I nodded but Dad; I must have looked like an idiot because I couldn't stop staring at her. Finally she just walked away and left me standing there."

Marshall took a deep breath. "And you're absolutely sure it was your mother?"

Hurt rose inside of Liam, but he quickly squashed it. Of course his dad wanted to be sure – he hadn't been there, he hadn't seen her. Liam nodded. "Someone called her 'Shannon'-" he saw his dad flinch and he hurried on. "And I did manage to snap out of my stupor long enough to take her picture."

"What? Did she see you do that?"

Liam shook his head. "I just took a quick profile shot as I ran out." He fished his phone out of his pocket and scrolled through his pics. "Here."

Marshall's hand shook as he took the phone and stared at the screen.

"Is it her?" Liam pressed him for an answer.

Marshall nodded, his throat tight. "Yes, it's Mary. This is your mother."

So many emotions swirled through Liam that he didn't know which one to voice. His eyes fluttered shut and his fists clenched as he tried to come to grips with the fact that he had indeed literally run into his mother forty-eight hours ago and she hadn't known him from Adam.

"Will?" Marshall called softly. "Are you all right?"

"Fuck, Dad! I don't know what I am," Liam snorted. "Sorry, I know you don't like it when I swear-"

"I'll let it slide this time – it perfectly sums up how you're feeling."

"Did you know she was in New York?"

Marshall shook his head. "No. I would have warned you if I knew – please believe that, Will."

Liam nodded. "I do, Dad – but I've had the feeling for years now that you did know where she was."

Marshall took another deep breath. "That's because I did."

Liam jumped to his feet. "What the hell, Dad? Didn't you think I deserved to know that kind of information?"

Marshall held up his hand. "Listen to me, Will. I wanted you to be old enough to go to her on your own, if you wanted to, to get the answers you seek."

"Wait, you mean you won't come with me?"

Marshall shook his head. "No, Mary knows where I am if she wants to talk to me."

"She knows where- you're saying she's a Marshal too?"

"I can't tell you that."

Liam rolled his eyes. "You just did by not telling me."

Marshall shrugged. "If that's the way you want to interpret what I said-"

Liam strode forward and hit his palm on the desk. "Damnit, Dad! Don't you want answers? Aren't there questions you want to ask her after all these years?"

"Of course. But I have time. You're off to Harvard in the fall and if you want answers and to make a connection with your mother-"

"Whoa!" Liam reared back on his heels. "Who says I want to connect with her? She abandoned us! I just want to know why so I can give you and me some closure."

Marshall sighed. "Life isn't that black and white, Son. There are so many shades of gray – you're going to find that out the hard way if you think you can just go to Miami, ask your mother why she left, and then you can leave her, no muss no fuss."

"That sounds good to me." Liam paused in the doorway. "She lives in Miami?"

Marshall nodded. "Currently – and when she's not on the road for her job."

"How will I catch her at home then?"

"For starters, I think you should wait til school's out for the summer."

"And then?"

"Then I'll plan a vacation for you – and don't worry, I'll make sure your mom's home."

"How?"

Marshall grinned. "By doing my job."

A/N: For any of you who are confused, Liam's name is William Mann - his friends call him Liam but Marshall and Rosa call him Will. Also, if anyone thinks Marshall isn't mad at Mary - think again.

Thoughts? Want more? Reviews are LOVE - and keep me writing! ;)