Annie requests that she be allowed to treat Helen as she thinks is best, which of course brings her into conflict with the Captain and the way that he perceives Annie is treating Helen. Annie proposes a somewhat radical course of treatment in order to teach Helen. She insists that if she is going to stay and work with Helen, that she needs to be allowed to completely isolate herself with Helen in the garden house for a full week. Annie plans on placing Helen in a position where she is fully dependent on her for everything. This, she reasons, will force her to communicate with Annie, which will enable her to assume the role of teacher for Helen.
Of course, Annie's proposal is somewhat extreme, and this is clearly where the problem lies with Captain Keller, as he is rather suspicious of such unorthodox methods and cannot see the value in what Annie is proposing. In addition, Keller does not necessarily trust this strange woman who has entered his family's life and who is charged with his daughter's care. It is only after he is persuaded to give Annie what she wants that he is able to see her true value and skill in working with Helen.