Ferb was happy to try to help his brother. Alas, fate might've been against them this time as Phineas' allergies were quite difficult to control.
A lot of it was too much for the poor kid to handle. His giant, red, itchy eyes. His stuffy nose was also quite a bother for him. However, there was one thing that made his allergies absolutely insufferable for the triangular-headed 12 year old, which was sneezing.
As far as the brothers were concerned, Phineas only had two types of sneezes, both equally mortifying. One of them was the more destructive kind, aptly named the Sneezes of Doom. The other one was rather hilarious. Phineas and Ferb discovered it one day when Buford had taken Isabella's amulet. Phineas was determined to find it but Buford just laughed in his face and called him adorable. Phin sort of snapped and said "That's it! Izzy, you and I are gonna find that amulet. Then we'll see who's adorable…huh…huh…chew!" Silence lingered in the air for a few seconds. Suddenly, Isabella giggled and said "Aw, you sneeze like a kitten!" Ever since then, he preferred never to sneeze again.
Despite all of that, he still had allergies that he'd have to try to control. Ferb's thoughts were broken when he had spotted Phineas and Isabella finally. Well Ferb thought I sure hope this works…
Meanwhile, Phineas actually was doing fine…for the first 15 minutes of their date. He started casually rubbing his eyes, which had luckily gone unnoticed by Isabella. After about twenty more minutes of this, he started to panic as he felt a familiar tickle in his nose. He tried to disarm the inevitable by slowly breathing in and out through his nose, but to no avail. Luckily, he found Ferb hiding out in the bushes and scampered over to him.
"How are you holding up?" Ferb asked as he inspected Phineas. "Not badly actually. They just started acting up a little while ago." Suddenly, he stopped speaking and gained a scrunched-up pre-sneeze face. As his breath started to hitch, Ferb understood what was happening. He quickly pressed a tissue to his brother's nose right in time for Phin to sneeze. "HuptCHOO!" Phineas sneezed.
Ferb was starting to worry. What if this just backfires? Ferb saw his poor brother snuffling miserably and was fueled with a fiery passion we have to try! "Are you okay now?" Phineas nodded. "Good, you'll need these for the rest of the time here." Ferb had two items in each hand: an eye dropper and a handkerchief. "Flush your eyes out with these eye drops. Also, if you have to sneeze, all you have to do is stifle into this handkerchief, ok?" Phineas nodded understandably. "Thanks bro!" He almost ran back to his girlfriend when "Wait!" Ferb stopped him. Phin looked back to find Ferb holding his left shoe. "Catch!" Ferb said as he passed his shoe off to his sneezy brother. He stumbled back as he was met with a flugelhorn note. Ferb chuckled behind his hand and dissipated into the green shrubbery.
As the Brit in the brushes followed his brother, he realized he might need to help his brother again. He carefully studied his brother's features. Phineas started to look a bit drained from his valiant effort to conceal his state. His eyes were a pinkish and looked itchy. He paled a bit in contrast to everyone else. He also noticed a steady rise of congestion in his voice. His nose was pink and sort of twitchy. He was sort of falling apart.
Ferb figured that the sooner he loses control, the sooner he can pull Phin out of there. So, Ferb decided to discreetly make his brother slip up so he can get a long deserved rest.
He started with gathering a few bouquets of wild flowers and weeds. Anytime, he came within a ten foot radius of Phineas, he'd wave them about wildly to stir up the air. From what he'd seen, it'd was working quite well. There was literally about a nanosecond of time between Phineas slipping up.
Suddenly, Ferb saw a superficial change. He saw Phineas quietly slip away again to hide behind a tree. Then he brought the handkerchief up to his mouth and nose. "EtCHOO! HiTCHEW! Ah-CHOOO!" Phineas let out an impressive fit that last lasted roughly three minutes. "33, 34, 35…" Ferb eventually counted 104 total sneezes, through 4 fits of least, not before Isabella found them both.
Isabella took a few seconds to absorb the situation before she sat down next to Phineas and started rubbing his back. When he was finished, he gave off a harsh yet quiet nose blow, reserved for the presence of a lady. Finally he stood up and stretched from his ordeal.
"Whew, that felt good." Phineas truthfully exclaimed as he sniffed and rubbed a finger under his nose. "Phineas, what happened back there?" Isabella asked calmly. Phineas looked around nervously. "What are you talking about?" Needless to say, she wasn't impressed. "Phineas, you were sneezing an awful lot back there. What happened?" She repeated. Phin was stammering nervously for an answer. "104 times to be precise." Ferb added as he finally came out of the bushes. Both saw that Phineas was essentially reduced to just a stammering, sniffing, sneezing mess. There were some closed doors that needed to be opened.
"You know you can tell me is something's up" Isabella's hands were intertwined with Phineas' hands. Finally, Phineas snapped. "Alright, alright!" Phineas shouted as he just wanted his girl to know the terrifyingly embarrassing truth. He solemnly walked away and came back a few seconds with a daisy. He simply brushed the flora over the underside of his nose. As a result, he quickly barked out seven harsh sneezes.
Isabella looked a tad confused. "As you can see, I didn't want my bad allergies to ruin the date. That's-Phineas was interrupted by his girlfriend embracing him and stroking his hair. "all." Isabella giggled at her boyfriend's silly attempt at the "perfect date". "Oh Phineas, that wouldn't ruin anything. All that needs to happen is that I'm spending time with you." Phineas was dumbfounded because of her answer. "But, you're not bothered by this at all?" "The only thing that'd make me uncomfortable about it is if you were miserable like today. Trust me we'll get through this together." Isabella happily kissed Phineas on the nose. "Besides, you do have a very cute, impressive sneeze." Isabella complimented. All Phineas could do was blush. "Phineas?" He looked up. "Catch!" she said as she threw her left shoe at him. Ferb laughed as he saw the perfect couple walk back home while he played "Ferb Latin" on his flugelhorn.