User.php

<?php

namespace App;

use Illuminate\Notifications\Notifiable;
use Illuminate\Foundation\Auth\User as Authenticatable;

class User extends Authenticatable
{
    use Notifiable;
    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = [
        'name', 'email', 'password',
    ];
    /**
     * The attributes that should be hidden for arrays.
     *
     * @var array
     */
    protected $hidden = [
        'password', 'remember_token',
    ];
    
    public function other()
    {
        return $this->belongsTo(Other::class);
    }

    public function getOtherAttribute()
    {
        if ($this->is_admin) {
            return $this->other()->get();
        } else {
            if (preg_match('/^get(.*)Attribute$/', __FUNCTION__, $matches) == 1) {
                throw RelationNotFoundException::make($this->getModel(), $matches[1]);
            } else {
                throw new Exception('Unknown exception.');
            }
        }
    }
}