[2.0] Getting controls in my controls

I have a custom user control that dynamically creates checkboxes and/or radio buttons as needed. Is it possible to register these created (sub)controls so that when I loop through the main forms control collection via .GetNextControl, it would not only hit my custom control container, but also the inner, created controls?
I suspect I'd have to give them a tabstop on the main form, but not exactly sure how to do that.

In the meantime, we've put a custom method in the control to do what we want, but I'd still like to know how to do this for future ref.

Thanks