any custom property that we want to append to any json/array representative from model.
p/s: laravel 5.1 above doc ref: https://laravel.com/docs/5.1/eloquent-serialization#appending-values-to-json s/o ref: https://stackoverflow.com/a/28560618/5866081
//in model Reply.php
protected $appends = ['favoritesCount'];
//so when data are being called from this model, element favoritesCount are included in the json/array
//another example from stackoverflow
class User extends Eloquent {
protected $appends = array('status');
public function getStatusAttribute() {
return 'someStatus';
}
}