Product::where(['product_id'=>$id])->with('category')
->with('user')
->with('productbrand.brand') // product has onetomany relation 'productbrand'
//with table productbrand and productbrand has onetoone relation 'brand'
//with table brand
->first();
$category = $show->category->category;
$username = $show->user->username;
$getbrands = $show->productbrand;