Can PyCharm Debugger, attaching to a local process, track subprocesses?

I know that the debugger, when run from withing PyCharm, is capable of also attaching and tracking to subprocesses, and that breakpoints work well there.

However, it doesn't seem to be able to also attach to and process subprocesses spawned by the `subprocess.call` command, when attaching the debugger to Python code being run outside of PyCharm.  Is this by-design, or an issue on my end?