LINQ Group Orderby Sub-Category Not Ascending?

How do I get the categorySub items to orderby ascending?

1.  'Category' item names appear ascending in the View
2.  'CategorySub' item names are NOT in any order.

var categories = from c in context.Categories
                               join s in context.CategorySubs on c.CategoryID equals s.CategoryID
                               let j = new CategoryViewModel { category = c, categorySub = s }
                               orderby s.Name ascending //Not Working...
                               group j by j.category.Name into g
                               select new Group<string, CategoryViewModel> { Key = g.Key, Values = g };