I am attempting to create a Gannt chart to manage project workflows. I would like to lock rows together for sorting purposes -- essentially, I want to sort by priority (high, low, medium), but keep the project's sub-tasks together. I've tried to use helper columns, but that's not working for me.

You can see in the image I've provided that I would need Project One to move as one unit, from initial edit to publish, and project two to move as a separate unit, from initial edit to publish. I want to sort based on the priority level, which is only a drop down option in the bolded project header row.

A number of people will be using this Excel doc and none of us are super Excel literate, so I would appreciate a simple solution if possible :) Thanks in advance!