The day before Hinata's seventeenth birthday, Hanabi doesn't appear at breakfast. Nothing is thought of it at first. She's been spending long periods of time hidden away in various places recently, studying a series of dusty scrolls, and tends to take her meals by herself as well so everyone assumes that's what happened.
Shortly before dinner though, a branch member raises the alarm. He's found her.
Few things could prepare Hinata for the sight of her sister sprawled on the floor unconscious, blood leaking out of her mouth. There are scrolls scattered on the floor around her, some covered in Hanabi's handwriting.
Her father is a tense presence next to her as he directs people to pile the scrolls to one side so that Hanabi can be moved.
Just before she's taken to the hospital, her hair falls away from her face and Hinata notices familiar bright green ink.
He's grim as he speaks again.
"No one talks about this," he orders.
Hiashi gazes at his younger daughter sleeping peacefully in the hospital bed. He understands that despite the Hokage being involved in her treatment personally, they had nearly lost her several times.
He frowns slightly. There are many good reasons why what she did was an incredibly foolish idea and he has no doubt that she would have known every one of them in depth. Not for the first time, he is forced to admit that her thought processes are a complete mystery to him.
"You confuse me," he admits quietly.
There is no response naturally and he sighs.
"Recover quickly so that I may tell you exactly how foolish you have been."
He thinks that the faint quirk of her lips at his statement is not entirely imagined and he leaves content.
Neji stares at his cousin as she lies in the hospital bed. He'd just got back from a mission with his team when he'd heard the news. He's not sure why he came to see her though.
Unlike her older sister, he's never really got to know her. She'd been a shadow peeking at his training sessions when she was younger, a pair of calculating eyes studying his every move but she'd been content to simply observe and he'd dismissed her as a bratty main house member.
Now, perhaps, he thinks that he had misjudged her. He has a feeling that he knows why she did what she had and he cannot help but admire her for it.
"Your loyalty to Hinata-sama is not misplaced."
He hesitates before touching her hand briefly. Her fingers twitch minutely.
"Hinata-sama would be... upset if you do not improve. Do so for her."
Hinata glances at her sister resting in the hospital bed.
She doesn't understand her sometimes. The girl who couldn't stand her had changed into one who'd do anything for her seemingly overnight and she hadn't noticed. She thinks that this makes her a failure as an older sister.
She doesn't deserve her sister's loyalty. She will never be a good clan head.
"You shouldn't have done that. I'm not worth it."
Unnoticed, Hanabi opens her eyes and glares at her.
"Stop that, nee-san. I had a plan and it worked."
"Imouto? You're awake?"
Hanabi smiles faintly and Hinata returns it after a moment.
Just a quick explanation of how the Caged Bird seal works for the purposes of this fic. Branch house members are sealed as young children (before they are allowed to activate their Byakugan for the first time). This is because the chakra pathways to their eyes are unused and thus malleable.
As Hanabi's eleven/twelve here and has been using her Byakugan for a number of years already, the seal is reconfiguring her (heavily used) pathways forcibly. If it had gone wrong, at best, she would have lost her ability to use the Byakugan, at worst, she might have ended up blind or even brain-dead from the backlash.
Hopefully that explanation makes sense.