Getting repeated fields via inheritance with GetFields()

I have a problem while working with GetFields() method while trying to get all the fields from a user defined class.

I have a parent class with, lets say two public fields, and another class that inherits from the parent and overrides one of the parent fields with the new keyword.

Problem comes when I use the GetFields method with the second class, because it's returning all the fields, including the overriden one. Is there something that I am doing wrong or a solution for only getting in this case the GoodBye field from the Parent class and the only one Hello field, the one from the inherited class?

This is a simple example of what I'm saying:

    public class Foo
    {
        public string Hello = "sdfsafda";

        public string GoodBye = string.Empty;
    }


    public class Bar : Foo
    {
        public new string Hello = "jl";
    }


    static void Main(string[] args)
    {

        var a = new Bar();



        var derp = new List<string>();

        foreach (var fieldInfo in a.GetType().GetFields())
        {

            derp.Add(fieldInfo.Name);

        }

        Console.WriteLine(derp.Count);
        // writes 3 instead of 2

    }

About using Properties instead of Fields, I'm afraid I can't use them right now because of limitations that are not in my hand to solve in the project I'm working on.