Nothing pushes Mr. Knightley to be more than civil and neighborly with the Woodhouses. But he goes way beyond that.

"Mr. Knightley, a sensible man about seven or eight-and-thirty, was not only a very old and intimate friend of the family, but particularly connected with it as the elder brother of Isabella's husband. He lived about a mile from Highbury, was a frequent visitor and always welcome, and at this time more welcome than usual, as coming directly from their mutual connections in London. He had returned to a late dinner after some days absence, and now walked up to Hartfield to say that all were well in Brunswick-square. It was a happy circumstance and animated Mr. Woodhouse for some time. Mr. Knightley had a cheerful manner which always did him good; and his many inquiries after "poor Isabella" and her children were answered most satisfactorily. When this was over, Mr. Woodhouse gratefully observed,

"It is very kind of you, Mr. Knightley, to come out at this late hour to call upon us. I am afraid you must have had a shocking walk."

"Not at all, sir. It is a beautiful, moonlight night; and so mild that I must draw back from your great fire."

In this passage, Mr. K is described as a very old and intimate friend who takes the liberty of visiting unannounced late in the evening. The degree of familiarity is pretty extreme and much beyond simple friendship or evening family relations.

We must therefore conclude that Mr. K goes to Hartfield for reasons other than civility or even because of a sense of family obligation. He must enjoy these visits and find them as necessary to his happiness as they are to that of Emma and DOMW. I'll have to keep that in mind as we read on. We are bound to find clues as to why he finds visiting Hartfield so enjoyable.

For the present, I will say that he enjoys the excentricities of DOMW. He is probably also very fond of the old man. I suspect he finds pleasure in brightening the old man's day, much in the way that Emma does her best to sustain her father's spirits. This may be source of bonding between him and Emma. Both find happiness in helping Mr. W. More later...