I do not own Phineas and Ferb. I only own my OCs, Maybelle and Misty Monogram.

Okay, so first off, this chapter features a pair of my OCs. If OCs aren't your thing, feel free to skip this chapter. I promise the last batch of chapters will feature Phineas and Ferb characters only.

Bit of background. A while ago, I wrote a story called Busting, Secret Agents and Kidnapped, where I introduced Maybelle and Misty Monogram, the sisters of Monty.

Since Cause We're Related is a collection of one-shots focussing on siblings, I decided to take out May and Misty and play with them again. Just think of this chapter as fitting in with my Busting universe. But you don't really need to read it in order to read this chapter.

Monogram Kids: Night Out

Though Monty had been home for a couple of years following his four-year stay at the prestigious High School Without a Cool Acronym, he still remembered the days of peaceful silence in his dorm room. There was no one to share his things with, no one to steal his food and no one to fight with.

Then he moved back home, and that all changed.

The twenty-one-year-old rummaged through the fridge, a soft scowl on his face when he didn't spot his leftover lasagna. "May-belle!" he hollered, shutting the fridge door with more force than what was required. "Where's my leftover lasagna?"

His seventeen-year-old sister appeared in the kitchen doorway, an irritated expression on her face. "I don't know. Have you tried looking?"

Monty shot her a look. "What do you think?"

Maybelle shrugged. "How should I know where it is? I didn't eat it, if that's what you're wondering. And don't call me Maybelle, Montgomery."

"Then who ate it?" demanded Monty. "I was going to eat it for lunch."

"I'm not your only sister, you know," May said dryly. Shifting her head slightly, she hollered, "Misty! Did you eat Monty's lasagna?"

"That was his?" their fourteen-year-old sister called back. "Sorry, I didn't know."

Monty let out a frustrated groan as May smirked. "That sucks."

"Note to self. Write my name on my food," muttered Monty. He went over to the pantry and pulled out a package of baked potato chips. "Or else the hounds will eat it up."

"I love how you automatically suspected me, by the way," said May, moving to sit in one of the leather kitchen stools that surrounded the marble table.

"Hey, it almost always is you," pointed out Monty. He sat across from his sister and tore open the bag of chips. "If you're not trying to irritate me you're attempting to get Misty in trouble."

"Not always," corrected May. "Just most of the time."

Misty skipped into the kitchen then, her short white hair just brushing her shoulders. "Sorry, bro," she apologized. "Should've asked who the food belonged to."

"Don't worry about it," dismissed Monty. "Just ask next time."

May crossed her arms. "And if I were the one who ate it, you'd have freaked out at me."

"She's the baby," said Monty with a shrug. "And you're a sarcastic, wisecracking pain in my butt."

"Before you guys get into another one of your famous bickering fits, I have a favour to ask you." Misty widened her blue eyes slightly and put a hopeful expression on her face. "There's this concert happening in South Jackson. Think you can help convince Dad to let me go?"

May snorted. "Please. There's no way he's going to let you go by yourself."

"I won't be by myself. I'm gonna go with some friends."

"Isn't it a little late to be asking Dad to go to a concert that's happening tonight?" asked Monty.

"Which is why I need some support. Please?"

"Sure," agreed Monty. "It can't hurt."

May rolled her eyes. "Of course you cave."

"Come on, she just wants to go to a concert," reasoned Monty. "We've been in her spot before."

Misty turned her pleading eyes onto her sister. May shook her head. "Sorry, but there's no chance. I know exactly what Dad is going to say. He's going to say the only way you can go is if one of us accompany you. I will not be that one."

Misty scowled as May got up and departed the kitchen. "You're a jerk!"

"Put it in the complaint box!" she retorted.

Huffing, Misty turned to shoot her brother a grateful smile. "Thanks, Monty."

Monty managed a smile. "No problem."

But inside he knew that May had a very good point. Their father would most likely only let his youngest child go if one of his older children went with her. And Monty had unwittingly offered himself as a willing chaperone.

Sometimes it sucks that she's smarter than me.

…

A few hours later, a heavy knocking sounded on May's bedroom door. Sighing, she marked her place in the book she was reading and set it aside. "Come in."

Monty and Misty quickly entered, crossing her pink-and-purple tiled floor to stand by her bedside. "We need to talk."

May arched an eyebrow. "Was I right?"

Misty groaned. "Yes, okay? You were right. Dad's not letting me go alone with my friends. He wants one of you to go with me. But I don't want you guys hanging with me and friends. No offense."

"Trust me, there's none taken," said May feelingly.

"So I've come up with an idea." Misty pressed her fingertips together. "We-wait." Her blue eyes suddenly sharpened. "Where's Frederick?"

Monty set his hands on his hips. "Where do you think?"

As the youngest Monogram child, Misty was the last to know about the work their father really did. So it came as a shock when she discovered that May's pet frog Frederick was a secret agent, but it didn't take her long to get used to the idea. Not after all the things she did with Phineas and Ferb.

"Hey, he's not always working," defended Misty. "I just wanted to make sure he wasn't lurking around. Okay, so my idea is that Monty drops me off at the concert. I meet up with my friends, have a good time, and let you know when to pick me up. We get home and Dad won't be the wiser!"

"And you're telling me this because…?" May asked suspiciously.

"I want you to come with me," spoke up Monty.

"Why?"

"I don't want to hang out in South Jackson by myself."

"And I don't want to be seen in public with you," quipped May.

Monty rolled his eyes in exasperation. "Can you please be serious?"

"Fine." May sat up a little straighter and pointed at her sister. "I'm gonna go ahead and put this idea in the 'Complete Failure' category." She then pointed at her brother. "What the heck is wrong with you? I know she's your favourite, but come on."

Misty frowned. "You guys haven't exactly been complete angels. Do I need to recount the story of how you found out about O.W.C.A to begin with?"

"No thanks, I was there, I lived it," said May dryly.

"She has a point," persuaded Monty. "We've both done some things behind our parents' backs. Now it's her turn."

"Uh…no. I think she's gotten away with enough."

"Alright, fine." The brunette crossed his arms. "You either come with me or I tell Dad what you and that Flynn girl did two weeks ago."

May glared. "What, they teach blackmail at O.W.C.A training now?"

"No. It's just Sibling 101."

"Fine." May threw her hands in the air. "Whatever. But I have a bad feeling about this."

Misty shrieked with glee and tackled her sister in a hug. "I love you!"

"Yeah, yeah."

Geez. The things I do.

…

After getting the rules iterated to them for the millionth time by their parents, the Monogram siblings were finally on the road. Monty was at the wheel of his black Buick, following his GPS' directions to Rojack Stadium, where the concert was being held. Misty bounced excitedly in the backseat, wearing her favourite red and black Pepper n' Spice shirt.

"I gotta know," started May, crossing her arms over her pink hoodie and glancing at her brother, "how the heck she convinced you to do this."

Monty shrugged. "She really wants this. And it's like she said, it's not like we haven't snuck around behind Dad's back to do what we want."

"Besides, it's perfect," chimed in Misty. "Dad won't send anyone to watch over us because we have Monty with us."

"Good point. There's no way Dad would think his golden boy would disobey him."

Monty shook his head. "You need to stop thinking Mom and Dad have favourites."

"Can't help it. I think its Middle Child Syndrome."

It took a couple of hours (and more than a few spats) but the trio finally arrived at Rojack Stadium. The parking lot was full of cars attempting to find a decent parking space. Misty pressed her face against the window and grinned. "I see them!"

Monty squinted out the windshield, soon locating a group of five young teenage girls clustered near the entrance. "Alright. Have fun, don't do anything stupid, let us know you're alive every hour with a text and call us when this whole thing is done."

"Got it. Thanks again!" Misty flew from the car and sprinted towards her friends. Monty managed to turn his car around and make his way back onto the street.

"So what are we supposed for the next three hours?" asked May.

"I think there's a mall around here somewhere."

After a few minutes of driving around, Monty finally found the mall he was looking for. This parking lot was considerably empty, so he parked close to the entrance. May stepped out and tucked her hair behind her ears. "You know, I'm half expecting Frederick to come jumping out and bust us. Or worse, Perry."

Monty grimaced. "Don't even joke." He locked his vehicle and the two headed for the entrance. Pushing through the double-glass doors, they were instantly greeted with a blast of frigid air. "Where do you wanna go?"

May locked eyes on the first store in her sights. "There's a drug store. We can get Misty new hair dye."

Monty could not help but laugh. "Very funny. It may not make sense, but she likes keeping her hair white."

"She's forever a mystery."

"I could say the same about you." Monty nudged her playfully. "You're always ragging on us."

"Well, you're always messing with me," countered May. "And Misty drives me crazy. Always getting away with stuff."

"Like you haven't gotten away with your own fair share of mischief," dismissed Monty.

"She gets away with much more than I ever have." May sighed. "I don't know. It's really hard being the middle child."

"Try being the oldest, having to look after two little pain-in-the-butt sisters," said Monty feelingly, sticking his hands into the pockets of his grey sweatshirt. "And I bet Misty has her own problems being the youngest. Dad didn't want her coming to this concert by herself because he still views her as the baby of the bunch."

"So there are problems all around. Doesn't help that Dad's line of business isn't entirely safe." May glanced at her brother with a slight smile. "But I guess that's why we have to stick together."

Monty slung an arm around her shoulders and squeezed. "You know it. Let's go see a movie or something."

"Sounds good. But I get to pick it out."

"Yeah. I don't think so. I'm the driver, and I'm the oldest."

May glared in irritation. "You're also the one who blackmailed me into coming with you guys."

"Even more reason to let me pick the movie." Monty grinned.

Surrendering, May allowed him to lead her into the theatre. After buying their tickets and some popcorn, they filed into the dark theatre. They had barely gotten through the first half of the movie when Monty's cellphone trilled.

"Shoot," he muttered, digging it out of his pocket and ignoring the glares of his fellow moviegoers. He then paled. "It's Dad!"

"Don't answer it!"

"What do you mean, don't answer it?" Monty rolled his eyes, stood up and rushed from the theatre. May hurried after him and when they were in the empty corridor Monty clicked the button. "Yeah?"

"Monty?"

"What's up?"

"Where are you?"

"What do you mean?" asked Monty in bemusement. "At the concert with Mist."

"How strange," Francis said calmly. "Because I just happened to turn the T.V to the channel where the concert is being broadcast live. And in the thousands of people in the audience, the camera happens to pause on Misty. And do you know what?"

"What?" asked Monty, trying to keep the nervousness out of his voice. It must have shown on his face, for May's eyes widened with panic.

"You and Maybelle are nowhere in sight."

"…we're in the bathroom."

"Oh really? So you can just run out and put Misty on the phone?"

"Uh…yeah. But it's a massive crowd. There's no seats or anything, you know. Gonna be hard to find her."

"Montgomery. Where's your sister?"

"Which one?" asked Monty, playing for time.

"Montgomery!"

"Alright!" Monty thrust the phone at his sister. "It's for you!"

"Hey, Dad," greeted May, pulling on the hem of her white skirt nervously. "What's up?"

"You're busted, that's what's up," snapped Francis.

May flinched. "Dang."

"Go get your sister, and come straight home," he ordered. "I swear, you better not waste any time. I will expect to see you in four hours. You three are in serious trouble!"

May's shoulders slumped as the dial tone buzzed in her ear. "We're busted," she informed, handing her brother back his cellphone.

"Have we been summoned by the Major?" Monty asked gloomily.

"You know it."

The two shuffled out of the theatre, May munching on her popcorn glumly. "You realize that as the older siblings we'll be getting most of the flak."

"Yup."

"She can't get away with this."

"She won't."

"We'll get her later?"

"We'll get her later," confirmed Monty.

Because even though Misty didn't necessarily force them into anything, she was the driving force behind the scheme she had concocted. And though she was the youngest, her older siblings were not going to take all the blame. Not without retaliation, at least.

But such was their relationship. As much as they stuck together, they also weren't afraid to strike down on one another.

And they wouldn't have it any other way.