That's good advice. If people think you did it on purpose they'll ask less questions than if you tried to hide it.

[But oh no, she's shaking. Tsuna can sympathize with being terrified and just wanting someone to tell you everything will be okay. He reaches out tentatively, and takes one of her hands in his own.]

Nia? Look at me.

[He waits until she is looking at him before he continues.]

You're not a doll. Someone with thoughts and feelings and people they care about who care about them couldn't be a doll. That's practically the definition of being a person.

[Wow, that was rambly. He shakes his head.]

Okay, I'm not... really good at this kind of thing, but.... don't say you're a doll anymore, okay? You're my friend.

[He's said something similar before, but he'll say it as many times as she needs to hear it.]