Binding to child member of BindingContext

Hi,

I'm wondering if there's a way to bind to the child of what I'm bound to already. Example, if my codebehind class has "BindingContext=this", in xaml, will I be able to bind to say, "this.ChildMember" for a given element?

in xaml:

<Entry 
      BindingContext="SomeChildPropertyOfExistingContext"
      Text="{Binding Text}" 
      />

So I have an object called MyPage - it has a whole bunch of things I want to bind to- and there's a section of the page that I'd like to bind to as its own independent element....

Thanks!
Mike