Drafts folder display in Mac Mail

I am running El Capitan on a MacBook Pro. All software is up to date. If I have a email I have created on a iDevice or iCloud on a PC and saved to Drafts then go to Mail on my Mac the drafts folder doesn’t show in the sidebar. If I search for the email it is present. If I then create a mail message on my Mac and save to drafts then the drafts folder appears in the sidebar and I can see both emails. When I delete the drafts and restart Mac mail the drafts folder has disappeared from the sidebar. I am using a iCloud email account with default settings. How do I get the drafts folder to stay in the sidebar.

Kevin