History Main / ObliviousYoungerSibling

* Sasuke from ''Manga/{{Naruto}}'' is unaware that Itachi killed his clan due to their planned coup d'etat so that the Hidden Leaf could be safe. When he found out, [[GoMadFromTheRevelation he did not]] [[DisproportionateRetribution take it]] [[{{Understatement}} very well]].

* Nunnally in ''Anime/CodeGeass'' missed that whole bit about her brother being TheStrategist for LaResistance during all those times when he was [[RichIdiotWithNoDayJob cutting class]]. Justified, since he goes out of his way to hide it from her. Although, the fact that she is very good at recognizing voices (being blind) yet does not recognize Zero's voice as her brother's despite the digital distortion being very slight does make her fairly oblivious.

* Carole Amherst, in ''MutantNinjaTurtlesGaiden'', thinks that her brother's funeral was staged and he's now become an actor who plays the role of a mutant turtle studying with fellow actor Raphael. If you think that's oblivious, read chapter six of the comic.

* In ''{{Sekirei}}'', the younger sibling is also a part of the plan, but doesn't know of her brother's involvement in it.
* Inverted and subverted in ''DeadmanWonderland''; [[spoiler: Yoh, the apparently oblivious ''older'' sibling, reveals he's known about his little sister Minatsuki's CuteAndPsycho tendencies all along, but wants to protect her anyway.]]

* Gioffre of ''TheBorgias'' doesn't seem to take any notice of the corrupt political world the rest of his family are embroiled in.

* Both of Chitose's "adopted" sisters in ''HappyLesson'' frequently handwave their brother's grouchy outbursts.
* Subverted in ''IchigoMashimaro'': Chika has no illusions about her elder sister Nobue. Still, the trope applies, as Nobue is the CoolBigSis to all four girls regardless.

* Shuuichi, the little stepbrother of [[NobleDemon Kurama]] in ''YuYuHakusho'', is completely oblivious to his brother's demonic heritage and supernatural activities. He's also presumably oblivious to the fact that he has a demon inside his body that can possess him, or that he's being used as a hostage to keep Kurama in line.

* Inverted in ''{{Kamichu}}''. Shoukichi is the only one that seems to realize just how weird everything is, including the cat's possession.

* Parodied in ''JohnnyDangerously'' when at one point the Pope (Creator/DomDeLuise) reminds all the neighborhood residents that Johnny's mom and brother think he's just a nightclub owner and not the notorious gangster Johnny Dangerously, and to keep the secret from them.
* Reuben of ''LittleOdessa'' knew about his brother's shady dealings, but apparently managed to put it out of his mind for most of the time and still looked up to him.

* Subverted with Gaz on ''InvaderZim'': she is perfectly aware that her older brother Dib is trying to thwart an alien invasion, she just doesn't care.

[[AC:{{Anime}} and {{Manga}}]]
* In ''LoveHina'', Kanako's [[RetCon fond memories]] of her stepbrother, Keitaro, makes her somewhat oblivious to his failures. But maybe sympathy, among [[BrotherSisterIncest other things]] clouds her judgement.
* ''Anime/{{S-cry-ed}}'' has the reverse situation, where Kanami seems oblivious to Kazuma's powerful Alter abilities and sees him as a kind-hearted layabout. It's later shown that Kazuma intentionally acts uncharacteristically pathetic around Kanami to encourage her to be more independent, apparently so that she'll have an easier time coping if the male half of their two-member family were to die violently.
* In ''DeathNote'', Sayu Yagami never finds out that her brother is really Kira.

* In ''Manga/OnePiece'', the older brother Ace is horrified and angry when Luffy [[spoiler:goes to [[TheAlcatraz Impel Down]] to rescue him]] because he believes that Luffy's just being the typical reckless, idiotic younger brother that he remembers that always made him worry.
** In an interesting inversion, Luffy himself at first [[spoiler: doesn't want to go to rescue his big brother after discovering his life is in danger via his burning [[ChekhovsGun Vivre Card]] and explains that his older brother is strong and wouldn't appreciate being rescued (it's also pointed out that if the person in danger gets out of danger, their Vivre Card returns to normal). It's only when he discovers that Ace is on death row that he decides to go rescue his brother.]]
* Nunnally in ''CodeGeass'' missed that whole bit about her brother being TheStrategist for LaResistance during all those times when he was [[RichIdiotWithNoDayJob cutting class]]. Justified, since he goes out of his way to hide it from her.
** Although, the fact that she is very good at recognising voices (being blind) yet does not recognise Zero's voice as her brother's despite the digital distortion being very slight does make her fairly oblivious.

* Sasuke from ''{{Manga/Naruto}}'' is unaware that Itachi killed his clan due to their planned coup d'etat so that the Hidden Leaf could be safe. When he found out, [[GoMadFromTheRevelation he did not]] [[DisproportionateRetribution take it]] [[{{Understatement}} very well]].

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* [[Literature/TheDresdenFiles Harry Dresden]] played this once in the novella ''Backup''. [[spoiler: It's told from the point of view of Thomas, Harry's older brother. A woman hires Harry to find a kidnapped child, pressing two of Harry's BerserkButton[=s=]. What Harry doesn't know is that the woman is a bad guy manipulating him into finding a book of rituals, that Harry will find with the child, and when he hands it over to the White Council, mass-producing the book will ''increase'' it's evil power, not diffuse it.]] Thomas, who can't tell this to Harry because of that very reason, has to pull all sorts of stunts to get things to work out okay, including letting Harry beat him up.

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* In ''Series/{{Noob}}'', one of the titular guild's members has a younger brother who has been playing the {{MMORPG}} in which the series is set much longer than him and reached a much higher level. He doesn't notice for quite a while despite the fact that they sometimes take turns on the same computer.

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* Sasuke from ''{{Manga/Naruto}}'' is unaware that Itachi killed his clan due to their planned coup d'etat so that the Hidden Leaf can be safe. When he found out, [[GoMadFromTheRevelation he did not]] [[DisproportionateRetribution take to well]].

* In ''Disney/{{Frozen}}'', Anna is oblivious to her older sister Elsa's ice powers until she exposes them at her coronation ball. Justified since Anna used to be aware of her powers when they were kids, but Elsa accidentally hurt her, so she was taken to some trolls for her to be healed. Part of the healing process involved memories of Elsa's magic being wiped out.

* ''Series/{{Supernatural}}'': Even though Dean ''defines'' "morally shady," Sam is emphatic that he's more than a killer or a grunt and that he has looked up to Dean his entire life. He lets Dean take the lead in most aspects of their lives, trusts him absolutely (up until Season 9...) and craves Dean's approval. Sam's been shown to go a bit unhinged when he believes Dean has rejected him or that he's disappointed Dean, even though Sam is often Dean's MoralityPet and keeps Dean's most destructive tendencies at bay. Bear in mind that other characters' descriptions of Dean include "two steps away from being a serial killer."

* ''Series/{{Supernatural}}'': While not necessarily "oblivious" to this, Sam is this for Dean in many ways, including often being a MoralityPet and one side of a nearly crippling co-dependency between the brothers. Dean has openly admitted that he viewed Sam as a "snot-nosed kid to keep in line" long after Sam grew up and developed hunting skills only second to Dean's (and he arguably still sees Sam this way even now). When Dean has been at his lowest, Sam has been emphatic that he's always looked up to Dean and that Dean is not merely a killer or grunt. Sam has also been seen to trust Dean on an absolute level, and defers to Dean in most aspects of their lives, even when Dean seems to be in the wrong.

* ''Series/{{Supernatural}}'' While not necessarily "oblivious" to this, Sam is this for Dean in many ways, including often being a MoralityPet and one side of a relatively crippling co-dependency between the brothers. Dean has openly admitted that he viewed Sam as a "snot-nosed kid to keep in line" long after Sam grew up and developed hunting skills only second to Dean's. Sam tends to sustain Dean emotionally and keep his most destructive tendencies at bay. When Dean has been at his lowest, Sam has been emphatic that he's always looked up to Dean and that Dean is not merely a killer or grunt. Sam has also been seen to trust Dean on an absolute level, and defers to Dean in most aspects of their lives.
** [[spoiler: It's been noticed that the normally intelligent and perceptive Sam has been remarkably slow on the uptake as to how the MOC/First Blade are affecting his brother, mostly just glancing worriedly at Dean and gently broaching the topic on a few occasions. WordOfGod has suggested that when Sam found out about the MOC, he just kind of assumed Dean knew what he was doing and could handle it, and it's taken quite some time for Sam to fully grasp that neither of those things are true. There have been other factors at play as well, including a major rift between the brothers, but part of the issue seems to be that it hadn't occurred to Sam (who has often fought internal supernatural forces throughout the series) that Dean could be vulnerable to similar internal forces.]]

* ''Series/{{Supernatural}}'' Sam is this for Dean in many ways, including often being a MoralityPet and one side of a relatively crippling co-dependency between the brothers. Dean has openly admitted that he viewed Sam as a "snot-nosed kid to keep in line" long after Sam grew up and developed hunting skills only second to Dean's. While Dean overtly tries to look after now-adult Sam in many ways, Sam tends to emotionally sustain Dean through a lot of crap in their lives and keep Dean's most destructive tendencies at bay. When Dean has been at his lowest, Sam has been emphatic that he's always looked up to Dean and that Dean is not merely a killer or grunt.
** [[spoiler: It's been noticed that the normally intelligent and perceptive Sam has been remarkably slow on the uptake as to how the MOC/First Blade are [[affecting his brother TheDarkSide]] , mostly just glancing worriedly at Dean and gently broaching the topic on a few occasions. WordOfGod has suggested that when Sam found out about the MOC, he just kind of assumed Dean knew what he was doing and could handle it, and it's taken quite some time for Sam to fully grasp that neither of those things are true. There have been other factors at play as well, but part of the issue seems to be that it hadn't occurred to Sam (who has often fought internal supernatural forces throughout the series) that Dean could be vulnerable to similar internal forces.]]

* ''Series/{{Supernatural}}'' [[spoiler: It's been noticed that the normally intelligent and perceptive Sam has been remarkably slow on the uptake as to how the MOC/First Blade are affecting his brother, mostly just glancing worriedly at Dean and gently broaching the topic on a few occasions. WordOfGod has suggested that when Sam found out about the MOC, he just kind of assumed Dean knew what he was doing and could handle it, and it's taken quite some time for Sam to fully grasp that neither of those things are true. There have been other factors at play as well, but part of the issue seems to be that it hadn't occurred to Sam (who has often fought internal supernatural forces throughout the series) that Dean could be vulnerable to similar internal forces.]]

* Yuzu in ''Manga/{{Bleach}}'' is similarly oblivious to her brother's powerful abilities and the supernatural activities and entities that surround them. This is most likely due to her faint spiritual awareness, especially in comparison to her sister Karin, who knows all about what Ichigo is and does.

* Mokuba Kaiba (''Anime/YuGiOh'') is absolutely devoted to his older brother, Seto. Indeed, he is the only regular character who calls Seto by his first name.
** Though he's not exactly oblivious in either the manga or anime.
* Shuuichi, the little stepbrother of [[NobleDemon Kurama]] in ''YuYuHakusho'', is completely oblivious to his brother's demonic heritage and supernatural activities.

** In an interesting inversion, Luffy himself at first [[spoiler: doesn't want to go to rescue his big brother after discovering his life is in danger via his burning [[ChekhovsGun Vivre Card]] and explains that his older brother is strong and wouldn't appreciate being rescued. It's only when he discovers that Ace is on death row that he decides to go rescue his brother.]]

[[AC:WebOrginal]]
* In ''Series/{{Noob}}'', one of the titular guild's members has a younger brother who has been playing the {{MMORPG}} in which the series is set much longer than he has and reached a much higher level. He doesn't notice for quite a while despite the fact that they sometimes take turns on the same computer.

* In ''Series/{{Noob}}'', one of the titular guild's members has a younger brother who is also playing the MMORPG and has reached a higher level than his. He doesn't notice for quite a while despite the fact that they sometimes take turns on the same computer.
* Gioffre of ''TheBorgias'' doesn't seem to take any notice of the corrupt political world the rest of his family are embroiled in.

* In ''Anime/OnePiece'', the older brother Ace is horrified and angry when Luffy [[spoiler:goes to [[TheAlcatraz Impel Down]] to rescue him]] because he believes that Luffy's just being the typical reckless, idiotic younger brother that he remembers that always made him worry.

* ''{{S-cry-ed}}'' has the reverse situation, where Kanami seems oblivious to Kazuma's powerful Alter abilities and sees him as a kind-hearted layabout. It's later shown that Kazuma intentionally acts uncharacteristically pathetic around Kanami to encourage her to be more independent, apparently so that she'll have an easier time coping if the male half of their two-member family were to die violently.

* Pop Harukaze from ''OjamajoDoremi'', at least for the first half of season 1. Once she becomes an Ojamajo herself she subverts the trope both in regards of what's going on and later on, her relationship with Doremi.

* Partially subverted in ''{{Sekirei}}'' where the younger sibling is also a part of the plan, but doesn't know of her brother's involvement in it.

* In ''OnePiece'', the older brother Ace is horrified and angry when Luffy [[spoiler:goes to [[TheAlcatraz Impel Down]] to rescue him]] because he believes that Luffy's just being the typical reckless, idiotic younger brother that he remembers that always made him worry.