Mary is such a quiet child said aunt Lydia. It makes me wonder what will become of her which word would you give the sentence a negative tone if it replaced the word quiet, would it be disciplined, calm, reserved or sullen

Replacing the word "quiet" with "sullen" would give the sentence a negative tone. While "quiet" can simply imply a lack of noise or activity, "sullen" carries connotations of anger or resentment, suggesting a more negative demeanor.

So the revised sentence would read:

"Mary is such a sullen child," said Aunt Lydia. "It makes me wonder what will become of her."