Transparent background color in TGroupBox - DELPHI

Question

How can i set transparent background color in TGroupBox?

In my Delphi's form I have a GroupBox and a Panel (graphically overlaid).
I wrote a procedure to draw a gradient fill on the Panel using Rect. It works!
Now I have another problem: GroupBox backgound color descends from the Form but I wish it was the same of Panel. I can't put GroupBox into Panel because draw procedure fill the entire Panel area (also GroupBox).
Is there a way (by code) to set trasparent background color of GroupBox?

Answer 1

I solved setting at runtime the Parent property of the GroupBox.

Answer 2

set parentcolor of the groupbox to true