Datarow Insert Datarow between Rows

Datatable and Datarows Shows as this works fine up to here... 2013 2012 2011 When you click 2013 the months are suppose to display under 2013 and above 2012 but the months display below 2011. Looks like this Currently ... 2013 2012 2011 May June July August ... I want it to look like this ... 2013 May June July August 2012 2011 Does anybody have any idea on how to fix this ? arrayYear = arrayYear.Where(s => !string.IsNullOrEmpty(s)).ToArray(); arrayMonth = arrayMonth.Where(s => !string.IsNullOrEmpty(s)).ToArray(); DataSet ds = new DataSet("DS"); DataTable dtTimeline = ds.Tables.Add("tblTimeline"); dtTimeline.Columns.Add("Ti ...