If you use Visual Studio on Windows, you have one nice option for multi-process debugging: https://marketplace.visualstudio.com/items?itemName=vsdbgpla... - auto-attach the debugger to child processes as they are invoked. I've also found this good in the past for debugging some kinds of client/server setup by having a little wrapper program that runs the combination of clients and servers required on your local PC.

All the processes end up being debugging simultaneously in the same instance of the debugger, which I've found to make light work of certain types of annoying bug. You might need a mode where the timeouts are disabled though!