transfer dependency ability value usercontrol control inside it

i have usercontrol (composite control) shown following pseudo xaml code:

<usercontrol>
  <dockpanel>
    <textbox />
    <button />
  </dockpanel>
</usercontrol>

i tradition control garland places impression wpf style. impression sets credentials ability usercontrol color. nonetheless credentials tone drawn usercontrol's credentials surface, nonetheless i wish drawn wholly textbox control's background. i (color=red):

if i bond credentials ability usercontrol textbox control's credentials property, i following one:

now also paints credentials middle textbox control nonetheless credentials tone usercontrol still exists. there any ways mislay description usercontrol's background?