The parents, instead of applauding her, called her a noisy chatterbox and told her sharply that small girls should be seen and not heard.
Matilda by Roald Dahl
Chatterbox noun informal British English
Definition: Someone who never stops talking
Etymology - disputed, but 'chatter' agreed to be onomatopoeic - imitating rapid speech. 'Box' conveys the sense of a contained single unit.
When used: Chatterbox is most often used to describe a child (see Matilda above). References are often playful and affectionate, but may also indicate frustration: He's the class chatterbox!
First Usage: OED cites 1735, in the Daily Gazetteer.