History BigBrotherInstinct / LiveActionTV

* Series/{{Arrowverse}}:
** ''Series/{{Arrow}}'':
*** [[ComicBook/GreenArrow Oliver Queen]] is very protective of his younger sister, Thea. In the earlier seasons, he looks after her well-being in an almost obsessive fashion (e.g. stopping her from having sex and trying to curb her hard-drinking party lifestyle), which ends up straining their relationship until he finally comes clean to her about his vigilantism. Justified since the last time he saw her before the yacht incident, she was a young girl, so he continues seeing her that way after his return even though SheIsAllGrownUp. Reaches its climax in Season 3, when a flashback reveals that Oliver killed a drug dealer who sold drugs to (the then-underage) Thea, while in the present, after Thea gets mortally wounded by ComicBook/RasAlGhul, he [[HeroicSacrifice offers up himself]] to become the next Ra's in exchange for saving her life in the Lazarus Pit.
*** Oliver's best bud Tommy is also this to Thea. After getting wasted at a club, Thea is given a ride home by Tommy, then is comforted by him when Roy is kidnapped. It's implied that, during the time that Oliver was away, Tommy looked after Thea as something of a surrogate brother. Becomes poignant in Season 2, when we learn that Tommy ''is'' Thea's biological brother, as his father, Malcolm, fathered her with Moira.
** ''Series/{{The Flash|2014}}'': One of the first things Iris does when she learns that [[ComicBook/WallyWest Wally]] is her [[LongLostSibling long-lost younger brother]] is to discourage him from participating in Central City's drag race. When that doesn't work, she risks herself being put in the crosshairs of the organizers by blackmailing them to stop the race entirely.
** ''Series/{{Supergirl|2015}}'':
*** A sureway to rile Alex up is by threatening or endangering [[ComicBook/{{Supergirl}} Kara]]. This came from the time when the two grew up, as Alex essentially had to sacrifice her social life so she could keep an eye on and prevent Kara from being outed as an alien. Also goes both ways, as Kara, being the stronger sibling physically, is always mindful to keep Alex from harm's way during missions (technically, Kara is the older one of the two, thanks to being suspended for years in the Phantom Zone).
*** Despite being her baby cousin, [[Franchise/{{Superman}} Clark]] is this to Kara. He was the one who gave her a home when she crash-landed on Earth, after all. In the first season, it's shown that he regularly texts Kara to inquire about her feelings and saves her once when she is overpowered in a fight.

* In ''Series/{{Gotham}}'', this is one of Selina Kyle's defining traits. In her second episode, she tries to comfort a scared kid by telling him to "go for the eyes" if he's messed with by the villains of the week. She's the only friend Ivy Pepper has. When she meets Bruce Wayne, she tries to help him learn how to fight and roof-hop, as well as tries to protect him from the assassins sent after her and from [[spoiler: Silver St. Cloud]], who was sent to manipulate him. She [[spoiler: kills Reggie after he threatens Bruce.]] When she encounters her old friend Bridget Pike, she offers her shelter in her own safe place, tries to help her friend get money to escape town, and is prepared to throw down with Bridget's abusive "brothers" to rescue her friend. For all her rough exterior, her Big Sister Instinct has made her one of the more compassionate characters on the show.
* ''Series/GothamKnights2023'': In the first episode, Harper tries to make a deal with the cops to take the fall for Bruce Wayne's murder in exchange for her younger brother Cullen being set free. She's later overprotective to him, after having protected Cullen for a long time as much as she could, starting with from their [[AbusiveParents abusive father]]. After he pushes back against this, Harper apologizes and tells Cullen how much she admires his bravery, having seen Cullen can very definitely handle himself.

* ''Series/LoisAndClark'': The titular couple to Jimmy Olsen.

* In ''Series/{{Smallville}}'', while they are about the same age, Clark tends to have this towards [[PlatonicLifePartners Chloe]]. Very much justified given the first three guys she tries to date (not counting Clark himself) all tried to kill her ([[spoiler:Sean in ''Cool'', Justin in ''Crush'', Ian in ''Dichotic'']]). Also because he is [[PhysicalGod Superman]] and she is an ordinary girl who isn't even particularly good in combat.
** Even when they are adults and after [[spoiler:Chloe had her first marriage]], this behavior persisted. In ''Escape'', when Clark finds out [[spoiler:Oliver and Chloe are sleeping together]], he says that she [[BreakTheCutie has been through a lot]], and that [[spoiler:Oliver]] should never take her for granted. [[spoiler: Ollie]] then reminds Clark that Chloe is a grown woman at this point, and that she can handle herself, and that in any case, he'd never hurt her. It all works out, and [[spoiler: Ollie]]/Chloe and Clark/Lois become the two {{OfficialCouple}}s of the show, and -- rather adorably -- also become avid [[ShipperOnDeck Shippers on Deck]] for each other.
** With being six years older, and coupled with his LonelyRichKid past, Lex Luthor very frequently felt this way towards Clark Kent in the early seasons of the series. Even going as far as to sometimes going really far whenever the young farm boy was threatened or harmed.

* In ''Series/{{Wishbone}}'', Sam sees a teammate being picked on so she takes him under her wing and teaches him to play better.

* In ''Series/ReadyOrNot'', Busy’s older brothers can sometimes be a pain, but they do care about her and are protective of their [[TheBabyOfTheBunch little sister]].

** Ross and Monica bicker a lot and didn't always get along as kids (largely due to the ParentalFavoritism shown to Ross) but several episodes have shown that Ross will stand up for Monica. When she and Chandler start dating, Ross makes it clear repeatedly that while Chandler is his best friend it wouldn't stop Ross from kicking his ass if he ever hurt Monica.

* ''Series/{{Underground}}'':
** Noah is Henry's surrogate older brother and he'll do whatever he can to get him to freedom. [[spoiler: When Henry dies in a HeroicSacrifice to save the other runaways, Noah doesn't take it well ''at all'']].
** Sam and Rosalee will do anything to shield their baby brother James from the harsh realities of slavery. Both of them have taken [[ATasteOfTheLash whippings]] [[TakeMeInstead in his place]] on two separate occasions. Sam even offers up his life savings (and getting any money at all when you're a slave is quite a feat) to buy James' freedom. [[spoiler: That particular subplot ends horribly]].

** Robb gives a [[MySisterIsOffLimits disapproving look]] when his younger sister Sansa is attracted to {{JerkAss}} Joffrey Baratheon in "Winter is Coming". He stands his ground against three outlaws to protect his younger brother Bran in "A Golden Crown". Later, Robb breaks his stoic demeanor when confronting Rickard Karstark for murdering two young captive squires, yelling, "''They were BOYS!''" when Karstark tries to justify it. Robb personally executes Lord Karstark shortly afterward.

** ''Series/UltramanLeo'' has this between Gen and a boy named Tooru, as well as Tooru and his younger sister Kaoru. And of course, there's Leo with his actual brother Astra, to the degree that a major villain exploits their bond to pit them against the Ultra Brothers as part of a larger plan to destroy both the Earth and M-78.

* In ''Series/CobraKai'': [[spoiler: In the season 5 finale, the students Miyagi-Fang "protects the egg (Anthony [=LaRusso=])" when Anthony uploads the video incriminating Silver to Cobra Kai.]]

* Subverted in the ''Series/ColdCase'' episode "Shuffle, Ball Change". The victim's brother was simultaneously protective and fond of his younger brother, yet he derided his ambitions to be a dancer and ultimately murdered him in a fit of jealous rage over his impending success (along with grief over his own failure as a wrestler).

* ''Series/TheUmbrellaAcademy'': Pretty much all the siblings have this towards each other, though it’s never made clear who is older. Examples include Luther towards all of his siblings, due to seeing himself as a leader, Diego towards Allison and Klaus, Allison towards Klaus and Vanya, Klaus towards Five and Allison, Five towards all of his siblings due to [[OlderThanHeLooks chronologically being older than them]], Ben towards Klaus, and Vanya towards Five.

* ''Series/TheWalkingDead'': Merle has this regarding his younger brother, Daryl, who is also his MoralityPet.
* ''Series/{{Warehouse 13}}'': Both Pete and Myka, towards Claudia. Just try watching "Breakdown," and not awwwing a little. For her part, in Claudia's introductory episode, she breaks right into the freaking Warehouse and kidnaps one of the main characters in order to force him to help her rescue her brother Joshua, who was zapped into an interdimensional space (and not, as initially thought, killed) twelve years prior.

* ''Series/GothamKnights'': In the first episode, Harper tries to make a deal with the cops to take the fall for Bruce Wayne's murder in exchange for her younger brother Cullen being set free. She's later overprotective to him, after having protected Cullen for a long time as much as she could, starting with from their [[AbusiveParents abusive father]]. After he pushes back against this, Harper apologizes and tells Cullen how much she admires his bravery, having seen Cullen can very definitely handle himself.

* On the Creator/Syfy show ''Series/DarkMatter,'' this is most of the crew's reaction to Five, the [[EveryonesBabySister youngest member]] of the ''[[CoolStarship Raza]]'' and treated like such. [[TheLeader Two]] and [[TheLancer Six's]] Big Sister/Brother Instinct in particular is immediate (verging on PapaWolf in Six's case), whereas [[TheBigGuy Three's]] is gradual and much more reluctant but undeniable.

* ''Series/GothamKnights'': In the first episode, Harper tries to make a deal with the cops to take the fall for Bruce Wayne's murder in exchange for her younger brother Cullen being set free.

* In ''Series/CobraKai''. [[spoiler: In the season 5 finale, the students Miyagi-Fang "protects the egg (Anthony [=LaRusso=])" when Anthony uploads the video incriminating Silver to Cobra Kai.]]