I'm having a hard time understanding your question. By their nature the dependencies are designed to suppress alerts on child objects NPM knows that the parent is down. Instead of marking them as "Down" they are marked as "Unreachable" and no further attempts are supposed to be made to poll them until the parent comes back.
What alerts exactly are you getting when the parent goes down? Can you screenshot for me the trigger/reset conditions for the alerts you want to fix?
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