JSFiddle - React, Tailwind, and code Playground

JavaScript

var p = [
    { name : "Billy", age : 5 },
    { name : "Lucy", age : 31 },
    { name : "Jonny", age : 11 },
    { name : "Wolfgang", age : 78 },
    { name : "Robert", age : 23 }
];
var oldest = p[0];
var youngest = p[0];
p.forEach(function(person){
    if (oldest.age < person.age) { oldest = person; }
    if (person.age < youngest.age) { youngest = person; }
});
console.log(oldest, youngest);