Orphans get a disproportionate amount of attention from the plot of any given story, and is it any wonder why? Orphanhood is a plot gold mine.
Right up there with a propensity to stare wistfully out windows, orphans collect an alarming number of plot-relevant knick-knacks. They will usually be a necklace or locket, and generally be a clue to the orphan's family, though they may have some other plot purpose, but they will always be inherited from the family in question. Mysterious swords and the like are very common. If the trinket saves the orphan's life by blocking an attack, it's also a Pocket Protector. If it wards off evil, it's a Protective Charm. If it grants powers, it's a Magical Accessory.
Why living families are so lacking in portrait lockets and the like may forever remain a mystery.
- In the Golden Age Captain Marvel stories, Billy gets a Deathbed Confession from his childhood nurse, Sarah Primm, explaining that he has a twin sister, and is given half of a locket. He soon realizes that he recently met a girl, Mary Bromfield, who was wearing the other half. Unlike Billy, Mary was adopted by a nice, rich family who wind up taking him in too.
- In Marvel Comics, Kevin and Parnival Plunder were each given half of a silver medal while they were young. Kevin would soon after go missing. As adults, they met again as Ka-Zar and the Plunderer, realizing their identities after putting the two halves together. It turns out it's actually the a chunk of vibranium, the first of its kind, and that anyone who possesses it can make more and virtually rule the world. I.e., it's also a prime MacGuffin.
- Superman's spaceship can serve as this, as it often has significant information programmed in (including messages from his birth parents). Also, in some modern versions, his cape is actually made from his baby blanket, which is a super-strong Kryptonian material that won't suffer Clothing Damage.
- In the Call of Cthulhu board game Arkham Horror, the character Wendy Adams, the Orphan, starts with an Elder Sign. The Elder Sign is a powerful item capable of permanently sealing gates to the other worlds and having six in play wins the game.
- Dungeons & Dragons Fifth Edition includes the "Backgrounds" mechanic, in which what you were before you started adventuring grants you skills and equipment. The equipment granted by the "Urchin" background includes "a token to remember your parents by".
- Oliver! is an adaptation of Oliver Twist, so naturally this trope occurs in the musical.
- Likewise Annie's locket.
- A Funny Thing Happened on the Way to the Forum has the gaggle-of-geese rings Erronius gave to his children before pirates kidnapped them as children. This comes from the Plautus and Terence plays A Funny Thing was based on, and they got it from the works of Menander and other Hellenistic comedies.
- Joanna insists on bringing her reticule with her when she an Antony plan to run away during the song "Kiss Me" in Sweeney Todd: The Demon Barber of Fleet Street. He tells her he'll buy her a new one but she tells him it was "the only thing my mother gave me".
- Older Than Feudalism: In Euripides' play Ion, the orphan Ion was raised in a temple after his mother abandoned him, and the only clue to his true identity is the basket he was found in. His mother conveniently recognizes this basket just in time to prevent him from killing her, after she tried to assassinate him.
- The handbag in The Importance of Being Earnest. Also presumably in the film versions.
- Agatha's locket in the webcomic Girl Genius has pictures of her missing parents, and also suppresses her hereditarily strong mad scientist abilities which would otherwise bring unwanted attention to her.
- More recently, the locket serves to suppress the mind control abilities of her not-so-dead mother, Lucrezia Mongfish. You have to wonder if that wasn't really what it was made for in the first place, and the other thing just a side effect.
- Parodied in Guttersnipe, wherein Lil' Ragamuffin, the proud street urchin, admits to her pet rat that she wishes she could find her parents one day, and produces a locket with their pictures in it: her only clue to finding them. Rat then informs her that those are just the placeholder photos that come with the locket.
- Archipelago: Credenza was given a hairband with a skull on it, from the one person who had been a friend to her, while both were bound as a slave to the world's most psychotic submarine pirate, the same one who's raid killed her parents...
- The pendant Anak gave to her mother when they parted in Tower of God. After the latter gets murdered by the Royal Enforcement Division, the rookie agent, Ren, takes it for himself. Much, much later, he managers to lure Anak with the pendant.
- Tally from The Weave owns a locket, one half of which contains a miniature map that marks her original home, the other half a photo of baby Tally with her parents, though her father's face is strangely blurry on it.
- Gosalyn's lullaby in the pilot for Darkwing Duck.
- Esteban's medallion in The Mysterious Cities of Gold.
- In Futurama, the Warden of the Orphanarium has one belonging to Leela that he forgot about. It's simply a letter in an untranslatable alien language, but it serves a purpose beyond being a memento - it contributes to her parents' deception that Leela is a member of an unknown alien species rather than one of the persecuted sewer mutants from Earth.
- Although she's technically only half an orphan (her father Hakoda is still alive, but off fighting a war in another part of the world), Katara's grandmother's necklace functions as this on a couple of occasions in Avatar: The Last Airbender: lost on a prison platform, found by Zuko, used to track the band by scent, retrieved by Aang; revealed Gran-Gran Kanna's history with the Northern Water Tribe and the man who becomes Katara's waterbending master, Master Pakku... who is actually the one who made that necklace with his own hands, as a gift for Kanna when they were arranged to be married..
- In Batman: The Brave and the Bold, the same Captain Marvel trinket mentioned above is used, except here Billy seems to have had it long before he met his long-lost twin Mary.
- Quasimodo's medallion in The Magical Adventures of Quasimodo.
- In Defenders of the Earth, Kshin was carrying part of a map to a Lost City when Mandrake first met him. Unusually for this trope, this is not mentioned for most of the series and only becomes relevant when Kshin's grandfather (who feared his grandson was dead until he saw a picture of him with the other Defenders) turns up with the other half of the map.
- Voltron: Legendary Defender: Keith's Marmora knife, which once belonged to his long-lost mother and serves as proof of his Galra lineage.
- The Foundling Hospital in London has cabinets of these tokens, left by mothers surrendering their children in the 1700s. The tokens were carefully kept on file with the children's papers, but unfortunately most mothers never returned to claim their children for one reason or another, with a few notable exceptions.
- Happens in China: Author and journalist Xue Xinran "writes of mothers wanting to provide their children with legacy mementoes when they give them up for adoption: some write letters to their babies on their clothing; others leave their fingerprint in blood. But orphanages routinely toss the clothing out."
- The Romans used to think it tragic, but acceptable, to leave an infant you couldn't provide for, particularly girls, on the ancient Roman equivalent of the local garbage dump. But the parents would often leave the child with a necklace of charms, in the far-fetched hope that some noble family would stroll by and take the child in, and the child would grow up with the memento to remind them where they came from. They even wrote plays about it, with the storyline usually having the child growing up and searching for, and inevitably finding their birth parents.