C# Find ultimate parent with LINQ

I have a hierarchical object with the following structure:

public class Folder
{
    public Folder Parent { get; set; }
    public IList<Folder> Child { get; set; }
}

If the folder is a root folder, the Parent will be null. If the folder is not a root the parent is not null.

I need to find the Ultimate parent of a Folder, that means, the root folder (not null) if exists one.

I would refer to avoid the while loop if possible. I would like to get it done using Linq expressions if possible开发者_如何学JAVA.

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Why avoid the while loop if it is the fastest way to do it?

Folder root = myFolder;
while(root.Parent != null) root = myFolder.Parent;