Deserialize Json into Object

I'm trying to deserialize a JSON that I get from a WebRequest into an object, and this is being ridiculously difficult, I'm very beginner on cSharp but this is so simple in Java that I was expecting it to be more simple in CSharp, need help with this.

This is the form of the Object I want to Deserialie from the Json Text

 public class HierarchyGraphResponse {
         public bool error;
         public string response_msg;
         public Response response;
         public class Response {
             public List<Item> items;
             public int max_pages;
             public int max_items;
             public int page;
             public class Item {
                 public string parent;
                 public string child;
             }
         }
     }

PS: I already have tested some of the libraries in the AssetStore and I cant even get them to work, so if anyone knows how to do that also will be welcomed.