Ekapp/skolehjem/app/Resource.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Resource extends Model
{
    public function resourceExtension() {
        return $this->belongsTo("App\ResourceExtension");
    }

    public function resourceCategory() {
        return $this->hasOneThrough("App\ResourceCategory", "App\ResourceExtension");
    }
}