“‘I take what you said to me at noon as a declaration that you’ve never known him to be bad.’
She threw back her head; she had clearly, by this time, and very honestly, adopted an attitude. ‘Oh, never known him—I don't pretend that!’
I was upset again. ‘Then you have known him—?’
‘Yes indeed, miss, thank God!’
On reflection I accepted this. ‘You mean that a boy who never is—?’
‘Is no boy for me!’
I held her tighter. ‘You like them with the spirit to be naughty?’”

This early exchange between the governess and Mrs. Grose makes apparent Mrs. Grose’s role in the story as the governess’s confidant, but possibly one who keeps the other at arm’s length. In this instance, after Miles has been mysteriously expelled, the governess asks Mrs. Grose if Miles regularly misbehaves, and Mrs. Grose says no, then changes her story and concedes that she has known him to misbehave occasionally. However, she believes this is to be expected of young boys and says she wouldn’t want a perfectly behaved boy anyway. Though Mrs. Grose is content to be a sounding board for the governess, it’s clear she knows more than she lets on and doesn’t divulge all she knows immediately when prompted. That she’s withholding and contradictory raises the question of her reliability.

“‘So do I!’ I eagerly brought out. ‘But not to the degree to contaminate—'
‘To contaminate?’—my big word left her at a loss. I explained it. ‘To corrupt.’
She stared, taking my meaning in; but it produced in her an odd laugh. ‘Are you afraid he'll corrupt you?’”

This quote, a continuation of the previous conversation between the governess and Mrs. Grose, cultivates a particular dynamic between the two. When the governess uses the word “contaminate,” she assumes Mrs. Grose doesn’t respond because the word is unknown to her and that Mrs. Grose is less educated than she. The reader learns eventually that Mrs. Grose is indeed illiterate. Mrs. Grose’s lack of education influences the governess’s perception of her, and the governess often speaks to Mrs. Grose as if she is someone who is incapable of understanding the reality the women face. This causes the governess to largely look for solutions to the hauntings at Bly alone. Furthermore, this quote establishes the idea of contamination or corruption, and poses the question of whether the children are capable of such things, a question the governess will continue to wrestle with for the duration of the narrative.

“‘You're afraid—?’
I spoke boldly. ‘I’m afraid of HIM.’
Mrs. Grose's large face showed me, at this, for the first time, the faraway faint glimmer of a consciousness more acute: I somehow made out in it the delayed dawn of an idea I myself had not given her and that was as yet quite obscure to me.”

This quote from Chapter 5 makes it clear Mrs. Grose knows more about the situation than she is letting on. The governess’s reference to Peter Quint elicits a reaction from Mrs. Grose, one of recognition. Despite her lack of education, and the fact that the governess perceives Mrs. Grose to be less capable and less perceptive because of it, this exchange makes it clear there are certain things Mrs. Grose knows that the governess does not.