How do you think Laura Lyons will help Holmes and Watson discover the truth? Why will she want to help them? (chapter 10-12)

Holmes believes Laura Lyons is the one person in the village who can help them.

‘And now tell me the result of your visit to Mrs. Laura Lyons—it was not difficult for me to guess that it was to see her that you had gone, for I am already aware that she is the one person in Coombe Tracey who might be of service to us in the matter. In fact, if you had not gone to-day it is exceedingly probable that I should have gone to-morrow.’

Holmes believes that she will help them because of her close relationship with Stapleton, something Watson has not yet suspected.

'This is most important,’ said he when I had concluded. ‘It fills up a gap which I had been unable to bridge, in this most complex affair. You are aware, perhaps, that a close intimacy exists between this lady and the man Stapleton?’

‘I did not know of a close intimacy.’