People in this fandom like to single out one specific sibling as Just The Worst. Usually that’s Luther, but I’ve seen it with others, too. And here’s why that doesn’t work:
Luther locked Vanya up in a soundproofed room, ignored the advice of his siblings, and went into “take her down” mode instead of “let’s try and help her” mode once she snapped. He accused his siblings of murdering their own dad and often defended the man who abused them all for years.
Diego didn’t just push Vanya away—he pushed everyone away. His cutting remarks toward Vanya are the ones most often referenced, but he makes them toward everyone. He takes a dig at Allison’s divorce, makes a lewd remark about Luther’s body (of which he is incredibly self-conscious) and calls Klaus “stoner boy.” The only reason he’s given a pass for Klaus is because he’s shown to genuinely care for him, but that’s the lone exception. He also allowed his lust for revenge to distract him from the more important business of saving the world, not realizing or caring until the last minute that revenge would have been the opposite of what Eudora wanted.
Allison abused the hell out of her power, turning her own daughter into a puppet when she didn’t feel like being a proper parent and quite possibly mind-controlled Patrick into falling for her. She also allowed her emotions to get the better of her, lashing out at Vanya for the crime of trying to be nice.
Klaus hasn’t been sober in 17 years, as we’re well aware, but the darkest sides of his addiction are only hinted at in the show and rarely brought up by fans. Suffice it to say, the fact he’s been to prison, been in and out of rehab centers, and isn’t trusted by any of his siblings attest to many, many years of betraying his family to get high.
Five is a condescending asshole. Yes, he’s a 58-year-old man in a child’s body, but that in no way excuses the way he treats his siblings. Age and experience are no excuse for telling your brother “I don’t think I’m better than you, I know I am” or telling your newly-sober and still-fragile brother “You’d know that if you were actually sober.”
Ben doesn’t get as much screen time as the others, but that doesn’t mean he’s the only decent one. While it’s true he’s the only one who cares to try and push Klaus away from drug abuse, saying “Oh, waaahhh, I have it worse because I have to stay here and watch you be a dumbass” while Klaus is losing his mind to torture goes a step or three beyond tough love.
Vanya could have approached her siblings in private, told them how much they’d hurt her, and given them a chance to apologize. Instead, she decided to tell the world that they were all shitheads who had it better than she did, and played the victim when they hated her for it. She also took swipes at Allison, the only sibling making a concerted effort to be her friend, and ended life on Earth as we know it.
You see? You can’t single one sibling out as Just The Worst because, if you look at their actions objectively, they’re all Just The Worst. They’re all damaged by their upbringing, and they’ve all damaged each other. They’ve all done shitty things and have had shitty things done to them.
Now, you might be tempted to defend your favorite sibling, point out that they’re actually Just The Best. I’ve got both good and bad news for you, pal, because….
Luther not only tries to treat Vanya as an equal—giving her a chance to speak in family meetings, speaking to her and not over her—he accepts all his siblings unequivocally. He has no reaction to Klaus twirling around in a skirt, listens without judgement to Allison’s confessions of power abuse, makes no remarks about Delores. He apologizes quickly when he realizes accusing his siblings of murder was shitty, wrote poetry on the moon, and has great taste in 80s music.
Diego might be abrasive toward his siblings, but he sticks by a drunk and distraught Klaus long enough to figure out what’s wrong and is quick to empathize with Vanya when she too is locked up on suspicion alone. He tries to get Luther to recognize his own abuse as such, adores his mom, and, despite the stormy nature of their relationship, clearly treated Eudora well.
Allison is quick to realize she was wrong to mistreat her sister, both recently and as a child, and moves to make amends—and keeps it up even when Vanya purposely treats her poorly. She accepts responsibility for her power abuse and her spoiled attitude and defends the person who robbed her of her powers.
Klaus is probably the most empathetic of his siblings, and he’s not afraid to show it. Even when suffering, he takes the time to comfort Luther and defends him at the cost of his life. When he confronts Reginald, he doesn’t only bring up his own abuse—no, he calls Reggie on the carpet for how he treated all his children. Even after he’s been demoted to lookout, he discovers a new power because he wanted to protect his siblings.
Five survived over 30 years in a post-apocalyptic wasteland because he thought he might stand a chance at going back and preventing the deaths of his siblings. When he accepts the Handler’s offer, it’s with the understanding that she will ensure his siblings survive. Everything he does is motivated by the chance of keeping his siblings alive. If that’s not loyalty, then I don’t know what is.
Ben doesn’t have to stick with Klaus. We see him walk away and vanish while Diego ties him up. He chooses to stay with him, give him someone to talk to, and fight a losing battle to push him toward sobriety—and when Klaus is about to give up and relapse, he accepts none of that bullshit.
Vanya may have been excluded by her siblings all her life, but that doesn’t mean she doesn’t care about them. When Allison takes her to task for trying to be nice, she later calls to check up on her and make sure she’s okay. When she thinks she’s killed Allison, rather than running from consequences, she returns to the Academy just to apologize.
You can’t single one sibling out as Just The Best, either, because they’re all Just The Best. They’ve all done shitty things, but they’ve also done caring and even heroic things. They’ve all suffered and they’ve all made others suffer, but they’ve also tried to alleviate that suffering.
This show isn’t about one horrible sibling who makes their siblings’ lives hell. It’s about seven siblings, who are all horrible and all wonderful, trying to heal from the scars of their past. This show is best enjoyed when you take their flaws alongside their virtues, and appreciate them for the fantastically complex characters they are.