C# How to use OrderBy with a property on a nested class?

I have a IEnumerable collection of a class which I want to sort. One of the 开发者_高级运维properties I want to sort is in a nested class. What is the syntax to make this work? The code below shows what I am trying to do, although it does not work.

    AbsenceViewModel avm = new AbsenceViewModel();
    if (sort.Column != null)
    {
        if (sort.Column == "OtherLeaveName")
            avm.ListNames = avm.ListNames .OrderBy("NestedClass.Name", sort.Direction);
        else
            avm.ListNames = avm.ListNames (sort.Column, sort.Direction);
    }

So putting in "NestedClass.Name" doesn't work. What do I need to do instead?

avm.ListNames.OrderBy(x => x.NestedClass.Name)