Hi Chris,
You can turn ON/OFF the group of nested tables column header by using the NestedTableGroupOptions.ShowColumnHeaders property.
gridGroupingControl1.NestedTableGroupOptions.ShowColumnHeaders = false; //Hide the column header
gridGroupingControl1.NestedTableGroupOptions.ShowColumnHeaders = true; //Show the column header
And also you can use the ChildGroupOptions.ShowColumnHeader property to control look and feel of all inner groups column header.
this.groupingGrid1.ChildGroupOptions.ShowColumnHeaders = false;
Also refer to Essential Grid Evalution center for more details.
http://www.syncfusion.com/support/evalcenter/default.aspx?cNode=5Best regards,
Haneef