JSFiddle - React, Tailwind, and code Playground

JavaScript

var data1 = '{"a": "1", "b":"2"}';
var data2 = '{"c": "3", "d":"4"}';

var json1 = JSON.parse(data1);
var json2 = JSON.parse(data2);

var obj = $.extend({},json1,json2);
console.log(obj);