OnPaint() not being called for my custom control...!

[kupps]

I'm creating a series of controls that I need to draw myself. They are all derived from Control and each overrides OnPaint(). The main parent control paints itself fine. It maintains a list of the second-level controls and they paint fine too. Each of these second-level controls contain their own lists of third-level controls, that ideally will draw themselves too but at the moment, OnPaint(), does not get called for them. Seems strange that the other two classes are able to paint and this last one is not.