Tear Jerker / Phineas and Ferb

Isabella: Hey, Buford, are you...sweating out of your eyes?
Buford: ...No! I'm just cryin'!

"Aren't you too old to be crying over a show about kids passing their summer with crazy things?"
"Yeah, *sniff* yeah, we are..."

Examples from Across the 2nd Dimension go here. Examples from Candace Against the Universe go here.

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General

• Several songs throughout the series:
  • "Little Brothers". Even if it is Shaped Like Itself.
  • "Mom It's Your Birthday".
• Most of Phineas and Candace's brother/sister moments are accidental ones because for some reason, Ferb is almost never there.
  • On a related note, there's Candace's tendency to call just for Phineas when she needs help, even when Ferb is there and especially when he's the one who ends up saving her. Even worse, in "Gaming the System," when Candace thinks both the boys are dying, she runs to Phineas and holds him while he fizzles out, only thinking about Ferb once Phineas is gone.
    • On another related note, which isn't so much a tear jerker but a sweet sort of thing, is when Candace is in the boys' kiddie ride in one of the episodes. She eventually falls down a canyon after the engine sputters out... then she doesn't have another quarter to put in to power it up. She screams for Phineas to help her but who's the one who realizes she's falling and pretends to be a dancing little statue thing all just to get a quarter to save her? Ferb.
    • Bonus points for Ferb actually showing a bit of shock and fright at the sight of Candace falling to her doom right before he goes and saves her. Knowing that it takes so much for Ferb to show emotion is a subtle way of showing the sibling bond.
• At least until the end of the series, Candace will probably never stop trying to bust her brothers, even though she'll inevitably fail and go crazy with frustration each time. Not a tragedy, but still not a very happy life.
  • Even sadder, even if she ever does bust her brothers or find out why the inventions disappear each time. The writers will just undo that with either time travel, memory erasing, or All Just a Dream... over and over again keeping her in an endless cycle of never knowing the truth and looking more and more insane. Though when Linda "does" see the inventions, expect a memory erasing or ironic misunderstanding immediately afterwards. The writers are almost sadistic with this.
  • The real tragedy in this is that her life, and her interactions with her brothers, would be so much happier if she would learn to let things go and appreciate her brothers, both who come off as nicer and better people than she does, for who they are.
• Man, Dr. Doofenshmirtz had it rough as a kid. Sure, it's mostly Played for Laughs and he's not exactly the nicest guy, but...Having to set up your own "surprise birthday party", and spend most of your childhood as a Gnome? And the fact that that his parents never showed up for his own birth?! It's kind of hard not to feel for the guy. His daughter Vanessa even lampshades this, pointing out that Doof isn't actually EVIL; he just lashes out through what he thinks evil is, which is why so many of his plans amounted to Poke the Poodle even if they had succeeded. He has no real malevolence, in contrast to Alternate Doof from the other dimension, he's just angry because of his lonely and neglected childhood which sets up his Heel–Face Turn at the end of the series. Ultimately, he's a brilliant man who can work for the betterment of all mankind if he could only see past his pain.
• From the way they react whenever Candace joins in (willingly or unwillingly) it's evident that the boys really love spending time with their big sister, but most of the time she has no interest in hanging out with them, to the point of absolutely refusing to even have anything to do with them when she otherwise isn't trying to bust them.
• Goodbye, boys.
  • Phineas and Ferb was Disney's most successful show ever, to the point where it got a lot of exposure and goodwill from Disney in merch, attractions, online spinoffs, tours and even featuring the show's characters crossing over in games and merch with characters from the Disney Animated Canon.^note  You know they've hit it big, when the boys are in a photo◊ with Mickey Mouse himself Then suddenly it just stopped. Disney stopped promoting it, merchandise stopped being made, the attractions were closed, the online stuff taken down, and the show quietly concluded with little fanfare.^note Well almost. Disney XD did run a marathon for the entire show leading up to the finale For any longtime fans, seeing it all just fade away like it never happened is incredibly depressing.
    • Or Fridge Brilliance if you look at it as the show itself vanishing just like one of the boys' inventions.
    • However, this seems to be turning around as the show's popularity has remained strong enough to garner not one, but TWO more seasons!

Season 1

Mom's Birthday

• The part where Candace keeps picking up instruments to play for her mom on her birthday, only to have them vanish thanks to Doofenshmirtz's inator. Sure, it was Played for Laughs, but still.

It's About Time!

• Doof and Perry's plot. Even though it's full of Ho Yay, it's still heartbreaking.
  • This song just about sums it up.
• When Perry is hanging up his hat, it looks as if Carl is crying. The worst part? He's not breaking down crying, he's just crying, as if he's not trying to draw any attention to it.
• Candace lamenting all the things she'll miss by being trapped in the past, including that she'll never see Jeremy again.

Dude, We're Getting the Band Back Together

• Lawrence has forgotten his and Linda's wedding anniversary, and Linda spends much of the episode feeling forgotten by the man she's so clearly in love with. Lawrence, meanwhile, tries to fix this, but it literally goes up in smoke. In the end, when they make up, he presents her with the only thing to survive — a single half-burned rose.
• The Love Handel band members have severely drifted off in the years since Lawrence and Linda kissed at their concert, and feel like it doesn't matter if they get along or not, because nobody cares about their music anymore.

Voyage to the Bottom of Buford

• The song. It's a tear-jerking song about a bully and his goldfish, full of fish puns!
  • Made exponentially worse if you, personally, have ever lost a pet fish (Or any pet for that matter) and can therefore relate quite directly to the song.
  • Watching this kid try to play ping pong with a fish is rather depressing.
  • Buford has proven to be a bully with sentiments and does like a few of the characters - his overwhelming crying over losing his goldfish is mostly played for laughs - but it's still crying, and it's from the bottom of his heart!

The Flying Fishmonger

• The Reveal that Grandpa Reginald Fletcher used to be a daredevil and adventurer in his younger years, much like his grandson and step-grandson. He's spent over sixty years sitting on his unfulfilled dream of jumping that gorge. Linda's even turned his bike into a lamp — it's a ridiculous image, but from Grandpa's perspective, it's pretty depressing.

Oil on Candace

• Django's giant painting being washed away before his father can see it. Fortunately, his father likes the regular-sized painting he made earlier just fine.

Phineas and Ferb Get Busted!

• The boys have both been heartlessly brainwashed, removing their creativity and imaginations (which may, in itself, be an example). They and Candace have been cornered by the Smile-Away sergeant, so their only means of escape are by building a bridge. Candace begs them to come to their senses, telling them that, despite the way she's treated them all summer, their creativity isn't bad but, in fact, the best thing about them and she's always secretly been proud to be their big sister. She then starts to sob and cries out "What have I done? WHAT HAVE I DONE?!". Slowly, Phineas blinks, then reaches forward to take the wrench from her hand. She looks up at him with tears running down her face. Phineas smiles and she smiles back. Granted this was all a dream within a dream, but it still shows she loves them. It’s hard not to give Ashley Tisdale credit for her painful performance in this scene.
• "Chains On Me" in the same episode is a slow, but catchy song, about Phineas and Ferb having their creativity and imagination slowly and cruelly stripped away from them.

Season 2

The Lake Nose Monster

• Though it's only momentary, Phineas is clearly very upset when he accidentally betrays Nosey, his voice cracking when he pleads for Nosey to return.

Tip of the Day

• "I have an ouchie. [points to his heart] In here." And this is right after Doofenshmirtz runs joyfully out of his room due to mistakenly thinking he had erased his humiliating incident from everyone's minds.

Attack of the 50-Foot Sister

• This episode really plays up Candace's teenage insecurity, and there are plenty of girls in the real world who can relate. On top of that, the two characters who want to use her to capitalize on other people's insecurities never face any repercussions for their actions, and are presumably still making their fortunes on exploiting people's self-doubts. The part where she starts crying after begging Phineas and Ferb to reverse her back to normal, though, is particularly sad:
  Candace: Can't you just make up some kind of reducing cream or an amazing shrink ray device?
  Phineas: Well, we'll see what we can do, but we're not magicians.
  Candace: I'm a freak. (starts to cry) I'll never be a Flawless Girl! (a single, giant tear drops from her face and falls to the ground as Ferb grabs an umbrella and puts it over him and Phineas to cover themselves) There's only one place where a girl like me will fit in: the oddball show! It was nice knowing you boys! Tell Mom and Dad I love them—from now on, I'll be living amongst the carnies! (tearfully runs off as Phineas and Ferb watch)

Chez Platypus

• The ending should count for Doofenshmirtz when the De-loveinator ended up zapping his date and making her feel nothing for him. And this was immediately after an "evil love song" and Doof saying he's never been so happy in his entire life. Not to mention that he had debated using it earlier but decided to throw the remote control away instead. Try re-watching it now that you're older.

Perry Lays An Egg

• Doofenshmirtz: "She left me for that trash-talking 35-ton pile of blubber. And broke my fragile, 10-ounce utterly-too-human heart."

Gaming the System

• The boys' Disney Deaths.
  Candace: ...Phineas?...Ferb?...Phineas! Ferb! NOOOOOOOOOOOOOOOOOOOOOO! (begins to cry)
  • Later becomes a Mood Whiplash because they have Video-Game Lives, but still.

The Chronicles of Meap

• "In a world... There. I said it. Happy?" If you don't understand it, this episode was dedicated in memory to Don LaFontaine, a voice actor famous for saying the quote in numerous movie trailers. This episode was also his last television appearance.

Thaddeus and Thor

• "Couldn't Kick My Way Right Into Her Heart" is partly as comically ridiculous as any other Doofenshmirtz backstory, but at the same time, very sad.
  • Yeah, he got Love Handel. He knows people.
• Candace feels genuinely embarrassed and humiliated when Phineas and Ferb show off their (apparently) shoddy fort, to the point where she storms out of the backyard even as Phineas tries to explain themselves. It's also worth noting that she doesn't try to bust them when Linda comes home and even calls their invention "amazing" at the end.
  Candace: What?! Have you lost your minds?! You've completely humiliated me in front of everyone!
  Phineas: But, Candace, this—
  Candace: Phineas, all summer long, you build the most amazing things, and the one time I reach out to you as a sister, the one time I count on you, you give me this?
  Phineas: But, Candace—
  Candace: No! Just leave me alone! (storms off) Excuse me!
  Phineas: Candace, wait!

Oh, There You Are, Perry

• The "Come Home Perry" song.
• The part where Perry leaves. The normally stoic Perry looks almost driven to tears when he is forced to relocate and leave his family behind.
• Candace desperately searching for Perry all over Danville because she thinks it's all her fault Perry's gone. The fact we know it isn't her fault at all makes it worse.

Finding Mary McGuffin

• It's already been listed as a CMoH, but "Not So Bad a Dad After All" has the potential to reduce watchers to an absolute wreck, particularly if the watcher has experience with a divorce or daddy issues— made infinitely worse if both criteria are met.

Not Phineas and Ferb

• This episode is A Day in the Limelight for Irving and adds a surprisingly sad dimension to his passion for Phineas and Ferb. Two brothers with an unbreakable bond going on great adventures together is certainly more appealing than his own summer with his Big Brother Bully.

Phineas and Ferb-Busters!

• Upon being replaced by a more advanced robot, Norm says, "Now I know I have a heart... because it's breaking."

Robot Rodeo

• In the room where Doof is working on his inator for L.O.V.E.M.U.F.F.I.N.'s contest, there are several pictures of scratched out inators on the wall. On one◊, he's written "I hate myself!"

The Beak

• Phineas is clearly uncomfortable with keeping secrets from Isabella, but has no choice but to do so, which leads Isabella to think Phineas is ignoring her and even acting somewhat selfishly for not helping fight Khaka Peu Peu. Probably the biggest thing in this regard is when Khaka Peu Peu comes towards the end, and he is forced to abandon her sadly, where Isabella's cries of "don't leave me!" pretty much cement this. In fact, this is probably the only episode where Isabella actually openly acts distant towards Phineas, and it's great seeing them resolve their issues at the end.

Nerds of a Feather

• "Ducky Momo is my Friend".
  • Most of the song is a Heartwarming Moment, but the end says that, while Candace still loves Ducky Momo, and loved him throughout her childhood, she is made fun of because she is now a teenager. This is made sadder due to the fact that it is true in real life. Still loving something that you loved when you were a child would get you mocked and teased when you get older.
  • The context is vague enough to be applied to LGBTQ people. Ouch.
    • And towards the end of the episode she doesn't even get to keep the Ducky Momo collectible she went to the convention to find.
      Oh, oh, but now the world just points and laughs at me here
      The hidden girl who risked so much to be here
      Showing my face is a no-no
      But Ducky Momo's still my friend!
• The meaningless Fandom Rivalry between the Space Adventure and Stumbleberry Phinkbat camps is one more wedge in Albert and Irving's relationship.

Candace Gets Busted

• The ending is right there in the title, but it's still a tough blow when it happens. And watching Candace saunter up to her room sadly is not pretty.
  Phineas: Candace, if it makes you feel any better, you accidentally threw the most outrageous party of the summer!
  Candace: (sadly) Thanks, guys. See you in a week.

Rollercoaster: The Musical!

• Though the "Rollercoaster" song is epic, it's clear from everyone except Phineas and Ferb (especially the former) that the ride is anything but fun. The passengers appear to be horrified of how intense the ride is, especially Isabella. If you look closely at her compared to the others, she looks genuinely scared and frightened as if thinking to herself, "I want to get off!"
  • She even looks toward Phineas in fright in the line "Not a written rule, but it's strongly implied."
  • Before the ride even begins, she asks, "Phineas, are you sure this is safe?" You can tell by her expression that she's completely anxious and horrified.

Season 3

Magic Carpet Ride

• Doof finds out that Roger took 20 years to re-make his painting, and that he felt bad for ruining it. This is mostly a Heartwarming Moment, considering how much of a Jerkass Roger normally is, but it becomes a tear jerker when Doof accidentally ruins it again. Then Doof gets so depressed that he tells Perry to do anything, as he doesn't care anymore.

Phineas and Ferb Interrupted

• We get to see the aftermath of one of Perry and Doof's fights: Doof is sitting in the middle of his lab next to the remains of his latest Inator, hugging his knees and crying. Really takes the fun out of all the other battles, seeing this poor man defeated for the millionth time by a small animal and crying all by himself next to the ruins of his latest creation. The fact that he spends the rest of the episode gleefully convinced that Perry has had a change of heart and wants to be partners only makes it worse.
• Boring!Phineas and Boring!Ferb horrify their sister and friends, and the audience along with them.

A Real Boy

• Norm. Just try not to feel terrible for that lovable 'killer robot man' during this episode. Especially at the end, when it looks like Doof is about to apologize to him. Given the show's (and Doof's) track record, you know what's coming, and it's simultaneously hilarious and heart breaking to hear "There's someone I always have considered family, and that person is... Perry the Platypus!". At least he took it well... since he was wearing Vanessa's headphones and couldn't actually hear him.
  Norm: Apology accepted... Dad!

Skiddley Whiffers

• This exchange:
  Vanessa: "I'm not a little girl anymore!"
  Doofensmirtz: "Well, you're my little girl!"

Bullseye!

• The first annual L.O.V.E.M.U.F.F.I.N. Pageant of Evil is being hosted, and the first event is about hurting an elderly woman's feelings. It's hard not to feel sorry for the old lady.

Phineas and Ferb and the Temple of Juatchadoon

• 1914!Isabella's betrayal of Ohio Flynn and Rhode Island Fletcher, even if it is undercut by a belated business card.

The Remains of the Platypus

• The sad look on Perry as he gets mindwiped and how he uses all of his remaining will to write “I fight evil“ gets me every time.

Let's Bounce

• Doof gets hit by his own Truthinator, which causes him to say "Secretly I'm very lonely."

Bully Bromance Breakup

• Buford and Baljeet "breaking up" over plastic. This sounds funny, and, for the most part, it is. That is, up until the song. While most "sad" songs in this show are merely Played for Laughs, we get Buford and Baljeet tearfully singing about missing each other, saying that there's a "bully sized/nerd shaped hole" in each of their hearts. Damn...

Meapless in Seattle

• This list has featured a break up between a bully and nerd, a girl who loves a duck, and a bully losing his fish. All of these things are certainly sad, but nothing, NOTHING, beats the unlikely tear jerk-ness of Balloony's death. Yes that's right. They can make you cry over a balloon popping. Note that said balloon has a creepy-looking Uncanny Valley face, and that still doesn't make it any easier to see it go.
• Upon thinking that everything is done for, Candace records a tearful farewell message for her mother on her phone. Yes, it is a reference to The Blair Witch Project, and yes, what she says does become a bit odd, but it is honestly, one of the most emotionally charged things she has said since her "I Know You're in There Somewhere" Fight in "Phineas and Ferb Get Busted".

Tri-State Treasure: Boot of Secrets

• Candace works so hard to get a rare Ducky Momo collectible at the swapmeet, though Doofenshmirtz's latest invention causes the final item to trade with the man with the collectible becomes new again (instead of rusty). The saddest part is that it wasn't anything that could affect the show itself, and fate just felt like being mean to her.
  • Especially harsh if you actually collect plushies or figurines. Moments like this can be too close to home.

Norm Unleashed

• All Norm wants is for Doofenshmirtz to love him. Even when Perry sends an energy blast at him, all Norm says is that he wonders if this is what a game of catch with Dr. Doofenshmirtz would be like.

Where's Perry?

• Perry having to stay behind to go on a mission while the Flynn-Fletcher family goes on vacation. Especially sad is Phineas' disappointment in not being able to bring Perry along.

Where's Perry? (Part Two)

• Continuing the trend of odd subject: We have a depressing soulful song about Candace ...leaving to live with monkeys.
  • The opening of the song is especially sad in context of Candace's character: her relationship with Jeremy is about the only thing that goes right in her life, and now she believes she's lost it and it's just too much for her to take.
  • Makes it even more depressing when you can relate to this song. Having people telling you what to think and being stressed out by society is the major issue teenagers are having these days. It really makes you want to live with monkeys!
• Robot!Candace's Heroic Sacrifice. And when the real Candace asks it why it decided to save her, it simply replies, "No Jeremy robot for me."

When Worlds Collide

• The bizarre but touching bond between Buford and Tristan the whalemingo, underscored by a weird but lovely song.

Road to Danville

• Doofenshmirtz's breakdown, as well as Perry being kicked off the bus due to no animals being allowed.
  • To elaborate on Doof's breakdown: He constantly repeats "It's all my fault! I'm a failure! I'm a failure!" as he sobs, meaning he actually thinks that the neglect he suffered from his family as a kid, his wife divorcing him and his daughter constantly being embarrassed by him is his own fault.
• At the beginning, Buford briefly lets slip how much he depends on the others' friendship. He's afraid that without them he'll turn into a 'cat kid' (the kid equivalent of a Crazy Cat Lady). Basically, he's sure that he'd go nuts without them, because no one else would ever hang out with him. Again, Buford is one lonely kid.

This Is Your Backstory

• Yes, it's a clipshow. A clipshow of Doofensmirtz's highly depressing life, where the true horribleness of his childhood, high-school years and love-life nearly makes him succumb to true evil... only to be stopped by the joy Vanessa and Perry bring him.
• Balloony dies for real. Made worse by the fact that it's only mentioned as an offhand remark.
• One flashback that doesn't come from any other episode is the story of Doofenshmirtz's immigration to the United States. His parents tricked him into going to town, and put him on a boat out of the country. It's underscored by the young Heinz's genuine excitement about a land of golden opportunity that welcomes misfits, only to wind up in America instead.

Season 4

Der Kinderlumper

• The Drusselsteinian fairy tale of the the Kinderlumper is nightmarish, because there is no way for a child to never do any of the behaviors listed (blinking your eyes, breathing in and out). Then we learn that this was just the version of the story Heinz was told by his mother. Roger was told to believe in the Kinderlumper as a Santa Claus like figure, and it's implied that's the more common version. Further evidence that Doofenshmirtz's parents are the real evil characters on this show.
  • Roger reveals to Doofenshmirtz that he still has the almond brittle that 'Der Kinderlumper' gave him. Almond brittle is Heinz's favorite treat, but Roger doesn't like it. So, in other words, his parents bought Doof's favorite treat and gave it to his brother just so that Doof wouldn't get it.

Sidetracked

• Doofenshmirtz feeling left out while Perry and Lyla are working together.
  Doofenshmirtz: This is why I'd rather not make friends. They find someone else, and BAM—you're alone.

Happy Birthday, Isabella

• After Stacy finds out that Perry is a secret agent, you can see he's upset about having to erase her mind. However, Stacy is able to invoke Loophole Abuse and Exact Words, and the two agree to keep her knowledge a secret. Perry's smile at that moment will bring tears.
  Stacy: Wait a minute—it says right here in your silly little pamphlet that if your host family finds out about your agent status, then anyone who's seen you has to have their memory erased, or you'll get relocated. Perry, I'm not part of your host family! ...I know, I know, it's a technicality. Look, I don't want Candace and the boys to lose you, but I also do not want my mind erased. I'm on the last ten minutes of that "Grievance" movie, and I don't want to have to watch that whole scary mess again. So, uh, can we just keep this a secret?
  (Perry grins and tips his hat to Stacy.)
• Isabella's song about how she just wants time with Phineas for her birthday. If you've spent a birthday away from your significant other, it is particularly heartbreaking.

Cheers for Fears

• The entire "It's All About You" sequence.

Father's Day

• Doofenshmirtz shows up to give his father their old lawn gnome back, but unfortunately it ends up breaking and Doof ends up leaving, feeling sad that he failed to impress his father (and that Roger once again gave his dad something better). However, Doof's dad then notices that one of the shards of the broken gnome ends up showing it's code, and Doof's father then accepts his gift by gluing it back together. His father actually appreciated something he did, but Doof will never know that.

Tales From the Resistance

• Candace-2 has trouble adjusting to a normal teenage life, even with Monogram's prompting. Ever since she was a little girl, she's known nothing but Doofenshmirtz-2's reign, and now that it's over, she feels like she's in a completely different reality.
• Isabella-2's reaction to learning that her beloved pet Pinky-2 was turned into a cyborg.
• Peter the Pandaborg's fate. While the other cyborg agents are freed from the Doofenshmirtz's control, Peter isn't as lucky, and escapes with the Doofenshmirtz's as their Brainwashed and Crazy Dragon and he can't do anything about it beyond hope he'll be saved like the others someday...

Act Your Age

• Understated one but one that's woven through the whole narrative: the gang will be splitting up, going to different colleges and pursuing different paths. Particularly sad to realize that Phineas and Ferb will be separated by an ocean instead of being able to come home and hang out in the backyard.
• Try to watch this Phineas and Isabella duet without bawling your eyes out. Even Swampy, one of the show's creators, couldn't stop himself from crying.
  • Particularly the look on Isabella's face as it ages them through Phineas ignoring her to work on inventions. The last image with her in it she looks absolutely devastated.
    • It's impossible not to watch this montage of Phinabella moments without thinking of the scene (even with the instrumental version playing in the background).
  • The entire premise of the show is the boys making every day of every summer count, and Phineas sings that his regret of never acting on his feelings for Isabella makes all those amazing, unbelievable, logic defying, once in a lifetime adventures seem like 10-11 years of wasted time.
    "And now our endless summer is finally coming to an end, I tried to make the most of everyday but now the years just seem misspent."
  • That was the line being sung while the aforementioned aging goes on. In the very last image, she's not there. And Phineas looks around as if he knows something is missing, but he can't figure out exactly what and it is heartbreaking.

Specials and Miscellaneous

Phineas and Ferb Christmas Vacation!

• The heartbreaking yet beautiful song entitled "Where Did We Go Wrong?", especially when you consider the fact that Phineas is hardly ever sad.
  • Jeremy sulking quietly in the snow. It's always when a secondary character gets enough love to appear in a group scene...
• The sheer heartbreak in Phineas' voice and face when Candace convinces him that he's the reason that Danville got branded naughty. Christmas is his favorite holiday and all he was trying to do was something nice for Santa, who he wants to be like. And now he believes that he ruined everything for everyone just because he wanted to do something nice.

Phineas and Ferb Summer Belongs to You!

• "The City of Love". It's the culmination of how many seasons of Isabella's frustrations and Phineas' freaking obliviousness. Her plaintive little voice, and the fact that he's still oblivious as she sings this right in front of him, are just sadness on overdrive.
  • Even worse: when the gang gets stranded on the island, Isabella cries while she admits her feelings to Ferb. What drives it home though is Alyson Stoner’s performance in this scene.
  Isabella: I just don't know what to do. We were in Paris; the most romantic city in the world, and (sobs) he didn't even notice me! (blows into handkerchief) I just feel like giving up... And look at him! [...] It's as if I don't exist!
  • The scene after this, where Phineas gives up hope. Watching this ever-optimistic kid who's never given up on anything before just completely fall apart, realizing he doesn't know what to do...there are no words.
    • "We could...we can...we can...we...we...we can't..." Hearing one of the biggest and most lovable optimists in modern television say those two simple words is nothing short of gut-wrenching. It’s also worth mentioning how heartbreaking Vincent Martella’s acting is in this scene.
• Vanessa leaves Ferb standing alone at the top of the Eiffel Tower holding a rose that he was going to give to her. Not quite tear-worthy, but still very sad.
  Ferb: She went off with someone else.
• Candace's whole situation is a mild version of this: for once her insecurities are actually played seriously, where she's honestly frightened that Jeremy might lose interest in her while he's in Paris, because she just doesn't think of herself as being very interesting. Then when she sees him in Paris, she feels even more pathetic, leading her to confess to Phineas how ordinary she feels compared to the boys, and how everything she's done has been a failure. It's resolved by Phineas giving her a pep talk and Jeremy calling her his girlfriend, but it really is sad to see how much her Butt-Monkey status actually affects her.

Phineas and Ferb: Mission Marvel

• Phineas' lack of tolerance for Candace's mistakes is really saddening (though it will probably be for different reasons for different people). She tries to apologize to him several times, but he is too frustrated at her to accept any apologies.
  • In particular, the part where Candace tries to talk to Ferb about it, only for Phineas to divert the attention of both of them is pretty sad.
  • "Only Trying to Help" is one of the most depressing songs the show has ever had. If you already feel bad for Candace and Isabella, then listening to them explain their feelings of rejection while watching flashbacks of what they have been through is just downright tugging at the heartstrings.
• Doofenshmirtz gets sidetracked for a few moments while he is introducing himself to the supervillains by the fact that no one wishes him well on his birthday.

Phineas and Ferb Save Summer

• Perry's sad face as he failed to stop Doofenshmirtz from moving the Earth away to an early autumn.
• Homeless Monogram.

Phineas and Ferb: Star Wars

• Some fridge sadness inevitably arises when you think about Isabella's status in this special. She's never met Phineas and Ferb, and she's brash and cold to the Firestar Girls, her best friends under normal circumstances. Her mother Vivian is nowhere to be found and even Pinky is gone, only alluded to by the name and design of her ship (side note: even by Star Wars standards, the Centennial Chihuahua is an enormous ship for a Crew of One). At least Han Solo has Chewie; Isabella is completely alone in the galaxy.
• While the lightsaber duel between Phineas and Darth Ferb was pretty awesome, think about how Phineas felt during it. He was forced to fight his Brainwashed and Crazy brother the whole time. One fan even drew a picture of the duel with Phineas crying.
  • Even before it, Phineas at first laughs when Darth Ferb proposes We Can Rule Together and then realizes Darth Ferb is not joking. He's in denial up to the lightsaber fight, trying to reason with his brother and repeating he doesn't want to fight Ferb.
    Phineas: Hey, this is. We would never want to hurt each other.
• The scene with everyone standing within the Death Star seconds before it blows up, with (seemingly) no chance of escape, as they think about any regrets they have, becomes much sadder after seeing Jyn & Cassian's eerily similar fate from Rogue One.

Night of the Living Pharmacists

• Doofenshmirtz, for all his efforts to be recognized, and his terrible childhood, being considered the default for "repulsive" by one of his own inventions.
• The Dwindling Party nature of the plot, and the reactions of the remaining characters being progressively more tear-jerking with each zombification.
• The scene where Isabella finally confesses her feelings to Phineas in particular hits pretty hard, as not only does Phineas pull a Heroic Sacrifice to protect her before he can reveal his response (which has her even visibly holding in tears when she watched it happen), but it is also implied that they forgot that moment as a result of being zombified.
• By the night's end, Phineas has seen his entire family get zombified. Losing Ferb at the climax nearly breaks him before Isabella reminds him that Ferb's only chance depends on them completing their mission. If there's any upside to the kids not being able to recall any further than building the vortex sprayer, it's that Phineas no longer has the memories of watching Candace and Ferb's transformations.

Last Day of Summer

• This is the series finale. Even the title has a sad feel to it.
• Even though Monogram rarely shows his appreciation for Carl, it turns out that he can barely keep himself together without the intern.
• After Doofenshmirtz outlaws thwarting when he takes over the Tri-State Area, he sends Perry out of his office because he already misses their usual routine. Perry's reaction tops that in heartbreaking potential: even his chatter sounds sadder than usual. Fridge Tear Jerking sets in when one realizes that Phineas and Ferb have already been removed from existence by that time, so Doofenshmirtz would have been his closest friend left.
• Doofensmhmirtz's reason for wanting to take over the Tri-State Area this time? So that his daughter won't think he's a loser.
• "Time Spent Together", accompanied by a montage of the main characters (and likely the audience) reminiscing over the show's best moments.
• That last scene of Phineas waving goodbye to the audience and shutting the door.

The O.W.C.A. Files

• This spoileriffic image. Perry the Platypus standing before what remains of the Flynn-Fletcher household.

Other

• At the end of the 2015 Comic-Con panel, Swampy breaks down while thanking all the fans for their support.
• This TikTok on the identity of Phineas' "real father" (it's Lawrence Fletcher) and the reactions to it from both Dan Povenmire and Swampy Marsh.
  Swampy: I just gotta be honest, I saw this this morning, and...this brought me to tears. This got it exactly right, and thank you. This has made my day, my week, my month. ^NoteSwampy Marsh is himself from a blended family, which inspired the family in the show.