I read a sentence in a chapter named "Going Places" which was:
"You told dad?" "She shook her head, chastened at his unawareness that he was always the first to share her secrets.
According to Oxford Dictionaries, "chasten" means - (of a rebuke or misfortune) have a restraining or moderating effect on. But I'm having trouble figuring out what it implies in the sentence.
You need to think about the relationship between Sophie (the narrator), Geoff (who asks "you told dad") and their father.
Sophie is surprised that Geoff doesn't realise that she would never have told their dad before telling him. And so she doesn't reply in words but is, for a moment silent, and only replies to Geoff's question by shaking her head. It is in the sense of "shocked to silence" that Sophie is "chastened". The surprise restrains her from talking for a moment.
