JSFiddle - React, Tailwind, and code Playground

JavaScript

function Person() {
    
}

Person.prototype.speak = function() {
   console.log("I am " + this.personName);
};
    
Person.prototype.runAnimals = function() {
    this.animals.each(function(animal){
       animal.run();
    })
};
    
function Animal() {
    
}

Animal.prototype.run = function() {
    console.log("My Animal " + this.animalName+ "  is running");
}

var persons =  [{personName:"John",animals:[{animalName:"cheetah"},{animalName:"giraffe"}]} , {personName:"Smith",animals:[{animalName:"cat"},{animalName:"dog"}]} ];

persons.each(function(person){
  person.__proto__ = Person.prototype;
  person.animals.each(function(animal){
    animal.__proto__ = Animal.prototype;
  });
});

persons.each(function(person){
  person.speak();
  person.runAnimals();  
});