test.js

class Parent {
  constructor(params) {
    Object.assign(this, params);
  }

  static fabric() {
    return new Parent({ source: 'fabric', test: 1 });
  }

  title() {
    return "I'm Parent";
  }
}

class Children extends Parent {
  title() {
    return "I'm Children";
  }
}

const parent = Parent.fabric();
const children = Children.fabric();

console.log(parent.title(), children.title());