Subitems in Stacked Bar Charts

I am currently using a stacked bar chart to show statuses across multiple boards. Instead of including my subitems in the board totals it breaks out subitems as their own series within the stacked bar chart (i.e. Board 1 and Subitems Board 1 are two different series in the bar chart). Is there a way to include the subitems on the board level within my stacked bar chart?