* The pilot has several sweet moments.
** For one, all of the other residents are nothing but welcoming to Bloo (unaware of what [[{{Jerkass}} a nuisance]] [[{{Flanderisation}} he'll eventually become]]). Wilt willingly forfeits his bed to him and Coco lays him an egg with a photo of Mac inside when she sees him having trouble sleeping.
** Mac keeping his promise to come back and visit Bloo at the house, proving Mr. Herriman wrong and prompting Frankie to continue trying to [[DefrostingTheIceQueen melt his frozen heart]].
--> '''Mr. Herriman''': It's just a cruel fact of life, Miss Franciss. Every child tires of their imaginary friend eventually.
--> ''(Frankie leans in and gives him a knowing grin)''
--> '''Frankie''': [[WhamLine Yours didn't]].
--> ''(Exits past a portrait of [[{{Foreshadowing}} the woman who eventually turns out to be Madame Foster]])''
* After the climax of "Destination Imagination", Frankie wants to free the antagonist, a RealityWarper with serious separation issues who'd destroy any would-be rescuers so long as Frankie stayed by his side. Mac, Bloo and the gang, who have just narrowly escaped his giant monster form, try to talk her out of it. Herriman, who has been absolutely brutal to Frankie (even moreso in this movie than throughout the rest of the series), tells her, "[[spoiler:Miss Frances, I have known you since you were a little girl. As I have watched you grow, I've been amazed at your lack of maturity, laziness, and lack of judgement. And all that time...I was wrong.]]" [[spoiler:He goes on to say that if Frankie wants to set him free, he trusts her judgement. Later, when the [[HeelFaceTurn villain-turned-good-kid]] tells Herriman Frankie is a wonderful person, Herriman lays his hand on her shoulder and agrees, "That she is."]] It's not as touching if you don't know the characters as well, but to any long-time fan of the series...OcularGushers [[CatchPhrase to the max]].
** Not to mention [[spoiler: Frankie sewing a body just for World so he doesn't have to jump around at everything all the time, and that the toy chest sort of becomes a playground for everyone at Foster's - with Herriman and Frankie shown to gleefully jump in too. It's wonderful.]]
* The ending of the episode ''Go Goo Go'' qualifies too. [=DI's=] just still happens to top it. But in case you're wondering how the ending of the former goes, Mac comes into the room where Goo is crying, asking if Goo is okay. It turns out that [[spoiler:Goo felt lonely and that's why she created all the [=IFs=]]]. Mac gave her a speech about how [[spoiler:imaginary friends are real friends and if she got to know the ones she already had then it would likely alleviate her feelings of loneliness]]. Mac, not realizing that the speech had cheered up Goo enough that she's already smiling, then apologizes for his MinorInsultMeltdown (the cause of her crying in the first place) and tells Goo that he wants to be friends with her--which causes an excited Goo to hug Mac. In the aftermath, Goo is finding homes for the [=IFs=] and has become the friend of the month as a result, while Mac has joined in on her wackiness.
* Herriman's 'Funny Bunny' routine, though funny and at times cringeworthily saccharine, is made really heartwarming by the fact that this is Mr. Herriman we're talking about. He's still Madame Foster's imaginary friend even after all those years. Awww.
** And even after all those years, he still sees her as that "sweet little girl." Double aww.
** After spending most of the episode considering the performance an OldShame and failing to prevent the footage of it from leaking onto the Internet, it turns out that the online viewers enjoyed it the same way Madame Foster enjoyed it (as opposed to laughing at him), so he starts performing it for the child customers. Triple awww.
* The ending of "Bye Bye Nerdy".
* ''Good Wilt Hunting'' TO THE MAX.
* ''The Sweet Stench of Sucess'', Bloo becomes a celebrity, but can't see his creator, Mac, which leaves Mac heartbroken. By the end of the episode, they meet up again, and even a {{Jerkass}} like Bloo admits that he loves Mac more than anything.
* No mention of "Who Let The Dogs In?" That moment near the end, before the happy twist, where Frankie gently takes the last puppy from Eduardo, sadly saying just "I'm sorry, Ed..." - and then Eduardo QUIETLY COVERING HIS EYES AS HIS SHOULDERS SAG...well, it takes a stronger man than This Troper not to find themselves on the verge of ManlyTears.
* Even though it was intended to be a funny moment, the [[BookEnds book end]] of the series was one for this troper. The opening animation shows the house being drawn, and the closing animation of the episode "Good-bye To Bloo" shows the house being un-drawn, as if to say "Thanks for watching, but all good things must come to an end." Followed by a thanks from CraigMcCracken and Creator/LaurenFaust in the closing credits.
* In "The Big Picture," Camery laments about not being able to be a part of the yearly Foster's Home photo because he's the one taking the photo. At the end of the episode, Herriman has a mirror-friend stand directly across from him, so he is in the photo.
* In "Busted," Bloo was under the threat of expulsion from the house from Herriman if he kept breaking the rules. After accidentally breaking Madam Foster's bust, Wilt offers to take the fall for Bloo, which he politely refuses. Considering that this was after Bloo's {{Flanderization}} started, you'd expect him to jump at Wilt's offer.
** At the end of the episode, when Bloo is found out, Mr. Herriman gets a little PetTheDog moment that reminds the audience that he's still a ReasonableAuthorityFigure at his core. At first, it seems he's going to discipline Bloo for breaking the bust, but it turns out that imaginary friends break it by accident all the time and that, since he had hundreds of duplicates made for speedy replacement, he assures Bloo that he had nothing to worry about.
* Although not heartwarming in the usual sense, the times throughout the series where Herriman and Frankie got along and worked together.
* In the pilot, after Bloo goes on a melodramatic (but still sincere) plea explaining him and Mac's situation to Herriman, the old fuzzball is silent for a moment, but relents and agrees to let Bloo in, clearly moved by their plight.
* Meta Example: In real life Tom Kane is an active adoption advocate, he and his wife have taken in many foster children. So when Mr. Herriman talks about finding new homes for imaginary friends, you know its coming from a sincere place.
* Seeing Mac, Goo, Bloo, Wilt, Coco, and Eduardo playing Pretend in "Make Believe It Or Not" will make you smile. It's just cute and funny to see the friends enthusiastically killing time on a rainy day with a childish game that goes over-the-top. The kids are being kids and the imaginary friends are being the playmates and best friends they were made to be. Brings one back to the days of childhood innocence.
* In a rare ''villainous'' example, there's a brief moment in "Seeing Red" when Terrence nearly cries TearsOfJoy as the titular Red goes to "SMASH BLOO!!!"
--> '''Terrence:''' ''[[SoProudOfYou "That's my boy..."]]''
** In the same episode, [[DependingOnTheWriter Bl]][[{{Jerkass}} oo]] actually ''apologizing'' to Red after he put him through so much misery for the entirety of their tour around Foster's after [[MyGodWhatHaveIDone realizing]] that Red was much, '''much''' different and was considerably ''nicer and softer'' than his [[{{Jerkass}} creator]].
* How well Mac and Bloo were getting along in "The Bloo Superdude and the Magic Potato of Power!" Mac was totally invested in that story!
* In the episode where they were taking a group photo of all the friends, it's demonstrated early on that Mr. Herriman is insistent on having everyone in alphabetical order, as shown when he denies Wilt's request to stand lower on the stairs so he can be seen. However, at the very end, he makes a single exception: [[spoiler: he tells a mirror imaginary friend to stand lower so the camera imaginary friend, who's taking the picture, can be in it as he's always wanted.]]
* When Uncle Pockets is discovered to be keeping mementos of his past adopters, he thinks this will end everyone's respect for him. The rest of Foster's is quick to say otherwise.
-->'''Mr. Herriman:''' That's preposterous! There is no shame in loving your child!
-->'''Madame Foster:''' ''(walks up to the pile and picks up a dolly)'' Collecting mementos is a wonderful endeavor!
-->'''Other Imaginary Friends:''' And to us you'll always be[=/=]the best imaginary friend ever!
* After Bloo has his HeelRealization in "Cuckoo for Coco Cards," he goes to apologize to Coco, and makes sure Coco knows he means it with this:
-->''(Having pulled out his stack of Coco Cards)'' Coco? I love these cards. I love them more then life itself! [[FriendOrIdolDecision But if they mean we can't be friends]], then... ''(Throws all the cards into the fireplace)''
* The "Let Your Hare Down" episode is an example of this, most particularly for Bloo. Even though that Frankie with Mac and the others had schemed with Bloo to do this, it's the simple fact that [[spoiler:Bloo goes through many different trials to try and make the normally uptight Mr. Herriman lighten up.]] Keep in mind, this is ''Bloo'' we are talking about; someone who's so selfish, he'd sell his friends (except ''maybe'' Mac) out if it meant satisfying his own desires... and he goes [[spoiler:through every possible fun thing he can think of just to see Mr. Herriman smile, ergo, he's doing something for not only his own benefit, but for Herriman's and those at Foster's who believed he needed to stop being so uptight.]]
** [[spoiler: Of course, Bloo does manage to succeed in getting Mr. Herriman to loosen up by unintentionally having the chickens attack him, however... it seems to work a ''[[GoneHorriblyRight little too well]]'' as Mr. Herriman takes loosing up [[UpToEleven way too far]], to the point that things like bills don't even matter to Herriman anymore.]]
* In ''My So-Called Wife'', Mr. Herriman was originally thought of as [[SarcasmMode being sarcastic]] when he said that he would get Mac and Bloo their own personal jet-cars, should the two decide to help Mr. Herriman with Coco. This is what he said to them, [[ExactWords "Sure, I'll get you a jet-car. No, wait, I'll get you]] ''[[ExactWords two]]'' [[ExactWords jet-cars!"]] While he ''was'' sarcastic about said jet-cars being in the mail, at the end of the episode, [[SubvertedTrope we see that he was being serious; Mac and Bloo have their own personal jet-cars, courtesy of Mr. Herriman.]] Herriman could have not done so, considering the whole charity event to Foster's was revealed to be nothing more than a fraud.
* Despite the episode itself being controversial, ''Foster's House for Make-Em-Up Pals'' did have a sweet moment at the end--when Goofball [[spoiler:turns out to actually be an imaginary friend and Frankie has to admit she was wrong, Goofball gives her a sincere thank you for taking care of him while he was there, something she's genuinely touched by. And given how much emphasis is placed on how thankless Frankie's job is, this must have meant a ''lot'' to her]].
* Heck, the series' entire opening sequence qualifies! After Foster's is drawn into existence, Mac walks up the house's stairs and meets up with Wilt, Coco, and Eduardo, who are all pleased to see him. We then cut to Bloo, who's just standing there bored, but is visibly happy to see Mac and we see all the friends laughing with joy.

!!Meta
* ''WesternAnimation/InsideOut'' is a film that features an imaginary friend - one who fears being forgotten forever, to boot - as a supporting character. After he saw it, Creator/CraigMcCracken gave his approval via Twitter, and followed it up with [[https://twitter.com/CrackMcCraigen/status/617228626300309505 "Also Bing Bong's welcome to stay at Foster's if he likes."]] At least two pieces of fanart were created in response: [[https://pbs.twimg.com/media/CJEc6OLUYAAFX6v.jpg one of Riley and Bing Bong arriving there,]] and [[https://pbs.twimg.com/media/CJEcWsuWoAEvJfw.jpg one where Bloo is about to excitedly show him around, saying that he'll blend right in.]]
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