What did herb clutters friends feel it was their responsibility to do, to help the family? Why?

I'm not sure how specific you want me to be. Certainly the Clutters had many friends in the community. Three of his closest fiends show up to clean the house after the murder. Of particular note is Alvin Dewey is the lead investigator on the Clutter case, and, as a former friend of Herb and Bonnie, he develops an obsessive interest in tracking down the perpetrators, sacrificing his physical and mental health for the six weeks they are at large. He lives in Garden City with his wife and two sons, and through Dewey we experience the many of the mixed emotions circulating in the town pertaining to the search, arrest, and trial of the two killers. His friends want the perpetraors caught with no negative secrets comming out about Herb or his family.