The "parent" is the module that caused the script to be interpreted (and cached), if any:
// $ node foo.js
console.log(module.parent); // `null`
// require('./foo')
console.log(module.parent); // `{ ... }`
What you're expecting is the "caller," which Node doesn't retain for you. For that, you'll need the exported function you're currently using to be a closure for the value.
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