JSFiddle - React, Tailwind, and code Playground

HTML

<div ng-app="testApp">
    <div ng-controller="navCtrl">
        <span>{{user}}</span> 
        <div ng-controller="loginCtrl"> 
            <span>{{user}}</span> 
            <input ng-model="user"></input> 
        </div> 
    </div>
</div>

JavaScript

angular.module( "testApp", [] );

var app = angular.module( "testApp" );

app.controller( "navCtrl", function ( $scope ) {

    $scope.user = "bahbahblacksheep";
    
} );

app.controller( "loginCtrl", function ( $scope ) {

    $scope.user = { name: "Fredrick Douglass" };
                   
} );