A/N: I do not own Phineas and Ferb. Do we really have to say that? It's a fanfic site, by definition this stuff doesn't belong to us, or it'd be canon. Anyway, while the thing I love most about Phineas is he would do anything for Candace and doesn't realize she's out to get him, I did wonder what would happen if he ever found out the sister he adores has been trying to "hurt" him all this time. Enjoy!

Part 1

Isabella skipped across the street and up to her neighbor's house. She pushed open the gate and saw her crush. She never quite understood how he became more attractive every day, but that was one question she was content to leave unanswered. "Hey Phineas!" she said cheerfully. "What'cha doin'?"

"We haven't decided yet," Phineas told her. "Ferb and I were just talking about that. Hey, it's been a while since you've picked something. Any requests?"

"Weeeeell," Isabella said slowly. "As it turns out, I'm really motivated to get my Harvesting An Exotic Fruit patch. The people at the Botanical Gardens promised us that we could come when their Dragonfruit crop was ready, and that was yesterday. The girls did tell me that, and invited me to go with them, but…"

She looked at Phineas, who was smiling expectantly, waiting for her to finish.

Isabella sighed and hung her head. "But I wanted to ride on the giant tire swing with you guys."

"Wow," Phineas said. "I'm sorry, Isabella, I had no idea you liked tire swings so much!" He didn't see the dirty look she gave him as he turned to his brother. "Ferb, I know what we're gonna do today! We're going to help Isabella get that patch! It's the least we can do to make up for yesterday. Hey, where's Perry?"

An hour or so later saw the backyard covered with several rows of vines that were producing kiwanos. The trio had invented a growth elixir, different than the one the boys had made to help Baljeet grow a giant watermelon. This one simply sped up the growing process. They were using fancy spraying machines to douse the fruit one last time, and then it would be ready for harvesting.

At that moment, Candace and Stacy walked out of the house. "I'm telling you Stacy, Slushy Dawg hasn't changed their recipe since they opened," Candace said. "It's right in their slogan!"

"If you say so," Stacy replied. "But the dawg I had last night tasted considerably slushier than it used to."

"Hold up," Candace said. "Phineas, WHAT are you guys doing?"

"We're helping Isabella earn a patch," Phineas replied.

"No, I mean what are you doing to the backyard?"

"Ooh, are those kiwanos?" Stacy asked. "How exotic!"

"Yeah, if you stick around for a minute you can try one!" Phineas said.

"Not if I have anything to say about it," Candace said, pulling out her phone. "I'm calling Mom."

Stacy walked over to Phineas, who handed her a fruit. "Hey, has anyone asked where Perry is yet?"

"Yeah, earlier this morning," Phineas told her.

"Shoot," Stacy said. "I'm almost never here in time to say it."

"Come back tomorrow, and we'll wait for you!" Phineas offered.

No one noticed the green beam that hit Candace just then. She slowly hung up before her mother had even answered, and dropped the phone. "No," she said. "You know what? Mom's not going to see it anyway. She never does, and you guys get away with it anyway. Well not today, today I do the busting, and if it gets me in trouble, so be it!"

Before anyone could quite process what she meant by that, Candace charged straight into the plants with a war cry. She tore them all out and began stomping on them.

"Candace, wait, what are you doing?" Phineas gasped.

"Candace!" Isabella cried.

"Woah," Stacy said. "I've never seen it this bad before."

"Candace, you're ruining them!" Phineas protested, but his sister wasn't listening. With more speed than one would have thought possible, she went through and trampled and destroyed every kiwano plant there was. When she was finished, she stood, heaving and sweating, before straightening up.

Everyone just stared at her in silence. "Okay!" Stacy finally said. "I have no idea where that came from, but I think this is something you guys need to figure out alone. I'll be at home if anyone needs me." She handed her kiwano back to Isabella, who took it without seeing it, and walked out the gate. "See ya."

"Candace, what the heck was that?" Phineas demanded. "That took us all morning, and we didn't even get a chance to get the fruit for Isabella's patch!"

Candace stared at what she'd done, then turned to Phineas. "I did it," she said. "I busted you guys! All by myself, without Mom!"

"Candace, why would you do something like that?" Isabella asked, with tears in her eyes. Phineas looked at her worriedly, than back at his sister with a frown.

"What do you mean why?" Candace asked. "Do you seriously mean to tell me you don't know that I've been trying to bust you guys all summer? Well, I mean, I'm sorry you got dragged into this Isabella, but my brothers have been doing dangerous inventions for too long now, and I finally decided to do something about it."

"What was so dangerous about planting kiwanos?" Phineas asked angrily.

"It wasn't about the stupid kiwanos!" Candace burst out. "It's that you made some sort of potion to speed up the growing, and used big dangerous machines to apply it! It's that if I'd tried to bring Mom here, you guys would have harvested and gotten rid of the fruit by the time she arrived. It's that you've been doing this kind of thing all summer, and I've been killing myself trying to get you in trouble for it, but no, you guys always get away with it, and I look like the fool."

Phineas' frown began to melt into a look of sadness. "I thought you liked our inventions," he said quietly. "I thought that was why you always wanted to know what we were doing, and why you wanted to show Mom."

"Seriously?" Candace said, almost screaming now. "Why couldn't I have had normal, dumb brothers? Why couldn't you and Ferb just have been normal, dumb kids doing normal, dumb stuff, like every other big sister has? I hope you never build another invention again, and then maybe you two won't embarrass me so much!"

Phineas opened his mouth, but then he shut it and bit his lip. He watched as Candace spun on her heel and walked into the house. Ferb put his hand on his brother's shoulder, and Isabella wrapped her arms around him. "Oh, Phineas…"

But Phineas gently broke away from them. "I'm sorry we couldn't get your patch, Isabella," he said quickly, and then ran into the house as well.

Isabella and Ferb shared a look, and then Ferb began to follow his brother. "Ferb?" Isabella asked. He turned and looked back at her. "It's okay that we couldn't get the patch," she said. "The Gardens can always let me know next time they have an exotic fruit. I'm really not worried about it…but I am worried about him. Let me know how he's doing later?"

Ferb nodded, and waved good-bye as she dejectedly walked back through the gate. He slowly trudged up the stairs, and could hear Candace in her room, saying impatiently, "Come on Stacy, pick up, pick up…" He went to his own room and pushed open the door, revealing all the lights turned off and the shades pulled down. Phineas was sitting huddled up on his bed, sniffling and clutching his knees. He didn't look up at Ferb, who sat down on his own bed.

Eventually Phineas spoke. "Did you know she was embarrassed of us?"

Ferb never wasted his words, but speaking to Phineas was never a waste. "Well," he said. "I suppose she did hint at that, but she seemed to enjoy herself so many times with us that I just assumed she was trying to be cool."

Phineas put his head in his hands. "We're terrible brothers," he said.

"No, we're not," Ferb said. "You know how sometimes she asks us not to do things that day? And we never do. We didn't know, if she'd just asked us to stop we would have." He was saying this to comfort Phineas, but deep down he knew that they'd continue building things if the president himself asked them to stop.

"But we should have known." Phineas looked up with a haunted look that killed Ferb to see. "I should have known. I should have seen that we were hurting her…am I really that oblivious of a person?"

Ferb didn't mean to think of Isabella right then, but he did and so couldn't truthfully answer that question. "Everyone's oblivious to some things," he said. "You have to make sure that you build an elaborate contraption every day that is both safe and legal, so who can blame you if other things slip through the cracks."

"She's my sister!" Phineas protested. "I don't want her to slip through the cracks!" Tears began forming in his eyes, and he quickly turned away. "From now on, I'll do what she wants. I'll never build anything again."

Ferb was startled, even though he didn't truly believe it, but he sat in silence, determined to stay there as long as was necessary.