linq & independent, реализуя equals & gethashcode

поэтому я пытаюсь заставить эту работу работать и не могу понять, почему она не работает

демонстрационный код;

namespace ConsoleApplication1
{
class Program
{
    static void Main(string[] args)
    {
        var myVar = new List<parent >();
        myVar.Add(new parent() { id = "id1", blah1 = "blah1", c1 = new child() { blah2 = "blah2", blah3 = "blah3" } });
        myVar.Add(new parent() { id = "id1", blah1 = "blah1", c1 = new child() { blah2 = "blah2", blah3 = "blah3" } });

        var test = myVar.Distinct();

        Console.ReadKey();

    }
}


public class parent : IEquatable<parent>
{
    public String id { get;set;}
    public String blah1 { get; set; }
    public child c1 { get; set; }

    public override int GetHashCode()
    {
        unchecked // Overflow is fine, just wrap
        {
            int hash = 17;
            // Suitable nullity checks etc, of course :)
            hash = hash * 23 + id.GetHashCode();
            hash = hash * 23 + blah1.GetHashCode();
            hash = hash * 23 + (c1 == null ? 0 : c1.GetHashCode());
            return hash;
        }
    }

    public bool Equals(parent other)
    {
        return object.Equals(id, other.id) &&
            object.Equals(blah1, other.blah1) &&
            object.Equals(c1, other.c1);
    }

}

public class child : IEquatable<child>
{
    public String blah2 { get; set; }
    public String blah3 { get; set; }

    public override int GetHashCode()
    {
        unchecked // Overflow is fine, just wrap
        {
            int hash = 17;
            // Suitable nullity checks etc, of course :)
            hash = hash * 23 + blah2.GetHashCode();
            hash = hash * 23 + blah3.GetHashCode();
            return hash;
        }
    }

    public bool Equals(child other)
    {
        return object.Equals(blah2, other.blah2) &&
            object.Equals(blah3, other.blah3);
    }

}
}

кто-нибудь мог обнаружить мои ошибки?