If the ribbons have already been merged, you can access the child RibbonGroups from the parent form.  The one issue here is that the keys for child RibbonTabs will have some text pre-pended to it in order to distinguish it from any RibbonTab on the parent that might have the same key.  To get around this, you will need to check to see if the RibbonTab's UnderlyingTab property is not null, and then check its key.  Your code will look something like this:

                foreach (RibbonTab tab in this.ultraToolbarsManager1.Ribbon.Tabs)
                {
                    if (tab.UnderlyingTab != null && tab.UnderlyingTab.Key == "childTab1")
                    {
                        tab.Groups["ribbonGroup2"].Visible = false;
                    }
                }

Hope this helps,

~Kim~

I am using NetAdvantage for Windows Forms version 2009.1. 

Also, I believe I failed to mention a couple things which may be the difference.  There is only one child form and it has a ribbon that merges in with the parent ribbon.  Under certain circumstances the ribbon groups on the child form's ribbon change (from visible to not visible).  I do not believe that I can access the data that I need from the parent form's tab activated event.  I am trying to take care of this in the form activated event right now within the child form.  Any suggestions?