Heartwarming Orphan

They're the characters the audience is predisposed to root for, suffering as they do from Parental Abandonment and a tragic childhood. They're the little orphan girls and boys who come into the story and proceed to melt the hearts of cranky old people and improve the lives of everyone around them just by being their cheerful, innocent orphan selves. The girls may turn out to be little princesses, and the boys might end up as Lords.

This, of course, is their Happy Ending after a terrible childhood of drudgery most likely spent in an orphanage or on the streets, or (shudder) under the care of their dear uncle or fond stepmother. If they have foster parents, or sometimes relatives, they can Earn Your Happy Ending by melting their cold and cantankerous hearts.

Heartwarming orphans don't have to do anything to be heartwarming. It seems inherent to their orphaned state. They don't even have to appear on stage. Announce that an orphanage has been destroyed, and A Million Is a Statistic does not come into play; obviously only a Complete Monster would do such a thing.

Of course, if they do certain things, they can lose the "heartwarming" part and end up with a somewhat less appealing role.

The exact opposite of the Evil Orphan. Contrast Conveniently an Orphan. If they look and act like characters from a Dickens novel, that's a Street Urchin.

See Orphan's Ordeal, Baker Street Regular.

Anime and Manga

 * Nadja Applefield from Ashita no Nadja, who travels around the world searching for her mother and helping others.
 * Yotsuba from Yotsuba&! is exactly this kind of person - as the main character. However, the series barely touches on her orphaned status, instead focusing on her daily life as a pre-school kid being raised by a (adoptive) single father.
 * 25th Baam has never met his parents, the closest thing to a mother figure to him would be his only friend/love interest Rachel.
 * Tohru Honda from Fruits Basket: a bit different from the others as she was orphaned while in high school, but it doesn't change the fact that her warmth helped heal the hearts of an entire dysfunctional family.
 * Hayate Yagami of Magical Girl Lyrical Nanoha, who turned four cold-blooded warriors into four kind-hearted people by being her cheerfully optimistic self. Though in a slight twist, they don't adopt her -- instead, she adopts them.
 * Lietchenstein from Axis Powers Hetalia is a bit like this, according to the published manga. Nothing is said about her original "family" and she's shown alone for quite a while, passing through lots of difficulties until Switzerland found her and took her in as his adoptive sister.
 * In the "Battle For America" strips, little America fits this as he is almost obscenely adorable and, when told to choose between England or France as an older brother, picks the former out of sympathy.
 * As for Liechtenstein, history suggests a relation to Austria, which fans have already considered. Then again, WW 1 forced him to abandon her...
 * Played with (with rather tragic results) in Pandora Hearts. Phillip is a very sweet little orphan kid whom everyone from the viewers to Oz seems to adore.
 * Suigintou before her Start of Darkness (in Rozen Maiden: Ouverture).
 * This, complete with Hair of Gold, was inverted all to hell in Monster. All. To. Hell.
 * Not completely. Johan may be evil incarnate but his twin sister, Nina, is a very kind and compassionate person as is Dieter.
 * Heartwarming Orphan protagonists have been a staple of the World Masterpiece Theater series, which adapted most of the classic examples listed under Literature into anime series.
 * Subverted big-time in Yu-Gi-Oh. Kaiba, the orphan with the horrible past (his parents die, none of his relatives want to take him in, he gets continually bullied during his time at the Orphanage of Fear, he finally gets adopted by ) ends up being one of the series' biggest Jerk Asses.
 * AND played straight, in a way, in that it makes him the Draco in Leather Pants. Besides, can one really question why someone would be a jerk after all of that? Not that it makes it any better.
 * His little brother Mokuba plays it straight though.
 * Serge Battour from Kaze to Ki no Uta.
 * In Wild Rose there's Camille, who was taken in by his parents' friend after they died. Not only does he look like an angel, but he's also prone to Tender Tears and just wants some love and attention from his diffident father figure Mikhail.
 * Candy Candy
 * Naruto is an orphan who has the tendency to make friends out of his enemies. Normally by spilling his life story out while beating them up.
 * Inuyasha: Rin was orphaned when bandits killed her family in front of her, leaving her mute and suffering nightmares. She lived as outcast in the village, being beaten whenever she was caught stealing food to survive. Then Kouga and his demon-wolves kill the entire village, including her. Then she's saved by Sesshoumaru who was testing his Healing Shiv to see if it worked. And then she follows him everywhere, regaining her zest for life, her ability to talk, while becoming his Morality Pet and melting hearts along the way: starting with his.

Comic Books

 * Incredibly common in British girls' comics of the period from around the 1960s to the late 1980s (by which time most of the comics had folded). One notable example was the highly-popular "Angel", set around an orphanage run by an angelic young woman who was herself an orphan.
 * Dick Grayson fits this trope to a T. Both Bruce and Alfred have commented that he brought joy and color back into their lives after he moved into Wayne Manor. Even as an adult, he's still pretty much universally loved by everyone who meets him, and still the best at softening Batman's heart.
 * The other Robins also fit this trope to varying degrees. With the exception of Jason, every Robin after Dick has had at least one living parent, but there's usually some form of Parental Abandonment at play.

Film

 * Lewis from Meet the Robinsons manages to win the hearts of the titular family, and even gets invited to join them, within a few scant hours of meeting them by...having low self-esteem and wearing funny hats?
 * In Despicable Me, we have the three girls Margo, Edith and Agnes being adopted by Gru.
 * Michael from The Blind Side.
 * Irena in The Way Back becomes something of a Morality Pet for the others in the group (seven escapees from a Siberian gulag). They all wind up papa wolves to her, but especially Mister Smith, before he himself was sent to the gulag. Unfortunately,
 * The Kung Fu Panda franchise has Tai Lung, Tigress and Po. All were adorable kids and while Tai Lung later betrayed his foster father in his adulthood, Tigress and Po have done theirs proud.
 * Brianna in Mystery Team

Literature

 * Poor little Jane Eyre is tormented by her cruel Aunt Reed and her three nasty children. Then she meets Mr. Rochester...
 * Heidi teaches Peter to read, makes the old grandmother more comfortable, helps Clara learn to walk, and makes her grandfather's life worth living.
 * Anne Shirley from Anne of Green Gables improves the lives of Matthew and Marilla Cuthbert by being a vivacious handful.
 * When Anne is in her late teens, Marilla also takes in a pair of twins, Davy and Dora Keith. Davy is rather Anne-like whereas Dora is the girl Marilla likely wished Anne was sometimes when she was younger.
 * In the third installment of the movie adaptation, which diverges horribly from the book series (it moves the series thirty years forward), Anne and Gilbert end up adopting Dominic, the son of a friend of Anne's who was killed helping her look for Gilbert, who was missing in action during WWI.
 * Sara Crewe from A Little Princess improves Becky's life and the life of the Indian Gentleman and spreads sweetness and imagination everywhere.
 * Mary from The Secret Garden makes the garden grow and improves her cousin's health.
 * Mary is actually a sort of subversion. She doesn't start as one of these, but more as an orphaned Spoiled Brat who has to go through quite the Character Development first.
 * As a Spoiled Brat, actually, she does Colin a lot of good, since she doesn't put up with his nonsense.
 * Tarzan is a grown-up example.
 * Oliver Twist, who just wants a little more gruel.
 * Harry Potter starts out as an orphan living in a closet under the stairs and ends up not only making Hermione's, Ron's and Hagrid's lives a little brighter, but also saving the world from You-Know-Who,.
 * Pollyanna, who is so unrelentingly cheerful that she earned a place in the dictionary.
 * Pretty much all the primary characters in Les Misérables are orphans. Or else raised by the Thenardiers, which probably counts anyway.
 * Cat of the Canals, aka, from A Song of Ice and Fire is an aversion, or maybe a subversion. She ends up joining at the age of nine.
 * Both subverted and played straight in Conn Iggulden's Emperor series. Marcus is effectively an orphan; his mother is alive, but she abandoned him in order to focus on her career as a prostitute. (Nice lady.) Marcus, however, is not the usual "heartwarming orphan"; his past affects his personality and gets in the way. Octavian also has a living mother but is an unruly street urchin until he is sent off to be raised by family. In his case, things turn out good, to say the least, seeing as he is adopted by
 * Susan Warner's 1850 bestseller The Wide, Wide World makes this one considerably Older Than Radio, and probably the Ur Example of the trope.
 * Oliver Twist, published in 1838, is more likely to be the Ur Example
 * In The Little White Horse, the orphaned heroine transforms her uncle, and even reconciles him with his true love.
 * Cheerily subverted in the Mechwarrior Dark Age novels where the resident Omnicidal Maniac "adopts" (read: found while strolling through a city that was recently razed by her instructions) a young girl. And she's changed! Now instead of wanting to just burn the known universe to the ground, she's going to burn the universe down for her!
 * Flute, in the David Eddings Elenium trilogy, is not really an example of this trope, but the band of knights who informally 'adopt' her think she is.
 * There are a handful of these to be found among the many orphans in Dear Enemy, the sequel to Daddy Long Legs. Sadie Kate and baby Allegra are perhaps the most direct examples of the trope. Sallie, the administrator of the orphanage where they live, admits she sometimes uses their heartwarming characteristics to charm donations of toys or clothing out of the wealthy and powerful.
 * A few of Jo's pupils at Plumfield, in Little Men, qualify for this trope.
 * Also by Louisa May Alcott are Eight Cousins and its sequel Rose in Bloom. Protagonist Rose Campbell, in the first, is orphaned and comes to brighten the life of her adoring guardian, lifelong bachelor Uncle Alec, as well as her seven male cousins and various other relations. In the second, adult Rose opens an orphanage called the Rose Garden, and personally adopts an orphaned toddler whom she names Dulcinea (after Don Quixote's lady).
 * Mark Herron, from Then There Were Five by Elizabeth Enright. He's extremely knowledgeable about the natural world, and teaches others about it.
 * Nello from A Dog of Flanders.
 * Freckles is older than normal in Gene Stratton Porter's Freckles but manages to pull off the role becoming Mc Lean's son substitute.
 * Parodied, along with many common Romance Novel Tropes, in PG Wodehouse's Genre Savvy short story "Honeysuckle Cottage".

Live Action TV

 * Punky Brewster makes cranky old Henry's life much more interesting.
 * Little Timmy from Lassie is an orphan who ends up adopted with the best dog in the world,.
 * In Friends, Phoebe is effectively an orphan after her mother kills herself; her father is still alive (as is her real mother - it's a long story), but he walked out on her before her mother's death. She'll use this to get whatever she wants, be it the last muffin or a date; her friends know she does this and will question her if she does it more than once a day.
 * There's a cameo in A Colbert Christmas: The Greatest Gift Of All from what appears to be a trio of heartwarming orphans asking for donations. Subverted in that they're actually Colbert's own children, begging the audience to buy the DVD so they can eat tonight.
 * Harry Hill's sketch show has the Poor Little Orphan Boy, who starts off cute but ends up screaming demands for games consoles and the like.
 * Jang Geum of Dae Jang Geum does something ingenious and heartwarming to save the day every second episode.
 * As with the Japanese drama version of A Little Princess, Shokojo Sera has Seira who lost her mother at a young age and her father to a mining incident. Yet, her determination to not let things get to her, even when she is mercilessly bullied and treated horribly by her previous classmates and the director of the school, is what shines the most.
 * This was a main component of memorable Hoarders participant "Sir Patrick"'s alleged backstory.
 * Boy Meets World had Tommy, a kid Eric befriends, though he eventually gets adopted by another family.
 * Merlin has one of these, a cute little boy whose father is killed on-screen, who is taken in by Morgana and Merlin, has large blue eyes and a timid expression, and who is eventually smuggled out of Camelot by Arthur. Then it's Subverted straight to hell when it turns out the cute little orphan that they've been risking their lives to protect is . Oops.

Newspaper Comics

 * Little Orphan Annie: Any character whose heart isn't warmed by little Annie is probably an irredeemable monster.

Opera

 * In Gilbert and Sullivan's The Pirates of Penzance, the pirates, who are themselves orphans, refuse to oppress any orphan. Word got around.

Theater

 * Annie: Little orphan Annie makes Daddy Warbucks' life much better through song and dance.
 * The title character of Sally.
 * Broadway Example/subversion: Little Sally, from Urinetown: The Musical, is apparently an orphan. She appears with Officer Lockstock during the narration scenes as well. However, she never really makes anyone's lives more cheerful. She does, but she suffers the same fate as the rest of the cast.

Video Games

 * Sunny, in the Metal Gear series, who lives up to her name so much that even perennial grouch Solid Snake loves her.
 * Flora from the Professor Layton games.
 * Cereza from Bayonetta.
 * The children from the Bassett orphanage in Solatorobo, who have a tendency of getting in trouble and needing to be saved. Two of the protagonists, Red and Chocolat are a fusion of this trope grown up a few years and fused with Happily Adopted (though they only adopted each other and apparently don't have any adoptive parents).
 * Part of Super Mario Galaxy's plot revealed Rosalina to be one of these.

Web Comics

 * Although Bob was present literally from the moment of her birth, Molly from The Inexplicable Adventures of Bob still qualifies on account of having no biological parents. She's okay with it, and will cheerfully say, "I'm adopted! It makes me special!" but she can still get very upset if a bully taunts her for having no real parents.
 * Goblin Hollow: How evil are these people? They had an orphange condemned.
 * Strays Meela. Uncommonly mouthy for it, but still awfully pitiful.

Western Animation

 * Kit Cloudkicker from Tale Spin is not only an excellent little buddy, but also a great surrogate brother to Molly.
 * Goselyn from Darkwing Duck certainly livens up her adoptive father's life.
 * Lilo from Lilo and Stitch befriends a psychotic alien lifeform. And we're with her.
 * Leela from Futurama is an orphan for all practical purposes; sadly, she doesn't seem to get much sympathy from it, and bringing it up may cause groans. She must have some of that mystique, though - she is the most beautiful and most accepted of her kind...
 * Also Tinny Tim, the small robot orphan who is seen now and then in Bender-related episodes.
 * How about ten Heartwarming Orphans? From "Jem and The Holograms", the Starlight Girls.
 * Little Robin Starling is such a heartwarming orphan that Tom and Jerry The Movie abandons its lead characters and gives the movie over to her.
 * Nibbles from the actual cartoons was rather heartwarming at times, if not a bit of a trouble-maker.
 * The unnamed little girl mistakenly named "Cancer" thanks to her medical bracelet by the inmates of Superjail. Naturally, this being Superjail, things turn out horrifically wrong. Also there's a subplot regarding her saccharine childhood innocence driving the warden mad because he's lost his. Then his inner child LITERALLY breaks out of his body and tries to kill her throughout the episode.
 * Patches and Poor Violet, who appear to have been transfered to Springfield from Dickensian London.
 * Anne-Marie from All Dogs Go to Heaven.
 * The eskimo boy Kunac in Batman And Mr Freeze Sub Zero.