in this state, this script doesn't interact with processes. It just monitor them and inform you when something append.
So 1. you can use this script to monitor your process stream, and wait for less zombie to continue, but that may not be what you want. I think your problem is somewhere else, related to wait or fork you should better rewrite tune your script to keep a clean control over it. Or at least detach from cron.
Did you check possible process number/resource/ulimit limitation ?
NB: look for zombie in Super search, it will help.
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