Child objects in domain class

I have a domain class like

public class Category
{
    [Key]
    public string IdCategory { get; set; }
    public string Name { get; set; }
    public List<Category> Children { get; set; }
    public List<Product> Products { 开发者_Python百科get; set; }



    public Category()
    {
        Products = new List<Product>();
        Children = new List<Category>();
    }

}

In the generated code I find the products collection, but not the children collection. There are some restriction about using the same class? There is another way to modeling this relation without recurring to keys?

---

public  class Category
    {
        [Key]
        public string IdCategory { get; set; }
        public string Name { get; set; }
        public string IdFather { get; set; }
        public List<Product> Products { get; set; }
        [Include]            
        [Association("ParentChild", "IdCategory", "IdFather")]
        public List<Category> Children { get; set; }




        public Category()
        {
            Products = new List<Product>();
            Children = new List<Category>();

        }
    }