When I have a parent control that has BackColorbut SystemColors.Control, but I have buttons in that parent control that I want to draw on the system. However, when I do not change the buttons BackColoron the buttons, it is drawn with the color of the parent. When I change a button BackColorto a button SystemColors.Control, it is no longer drawn in the Windows theme.

The left version is c SystemColors.Control, and the right one is unchanged BackColor.

Exploded, it looks like this. Here you can see that the buttons have a solid background.
Any suggestions how can I fix this?
The effect in the image can be achieved by creating a new .NET 2.0 WinForms project and changing the constructor Form1to the following:
public Form1()
{
InitializeComponent();
var textBox = new TextBox();
Controls.Add(textBox);
var button = new Button { Text = "L", Width = 23, Height = 18, Left = -1, Top = -1 };
textBox.Controls.Add(button);
button.BackColor = SystemColors.Control;
}