Silverlight Custom Property Inheritance

I have a class inheriting from UserControl, with a custom DependencyProperty. I put a stan开发者_如何学JAVAdard button inside (not necessarily it's immediate child) and I want to get the value of my custom DP on the button, like this:

usercontrol.MyDependency = "hello";
var x = button.GetValue(MyUserControl.MyDependencyProperty);

It's pretty much property inheritance inside the visual tree, but x is null, instead of "hello".

Is property inheritance like this possible in silverlight?

(And no, I do not want to put userControl into its own DataContext, I need the DC for my ViewModel, MyDependency is a property of the view, not the viewmodel)

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It is available to a few native properties only. And you cannot enable it for custom properties.