PHP - What is the best way to handle errors when access deep properties of deep objects?

I'm developing a project with complex model's relations (Laravel)
I have more than 10 tables with many foreign keys.
Now, I'm stuck to handle error when access a deep property through many levels of eloquent objects. Below is example of relations

    Category
       ||
       ||
    Product    ===     Seller    ===    User === Country === Region
       ||                ||              ||
       ||                ||              ||
      Cart          Seller Level        Buyer
       ||                                ||
       ||                                ||
     Invoice ==============================

Here is a simple script to get country of seller/buyer from specified invoice - Eloquent

$invoice = Invoice::find($id);
$countrySeller = $invoice->cart->product->seller->user->country; //6 levels
$countryBuyer = $invoice->buyer->user->country; // 4 levels

In a bad luck day, the script got error Trying to get property of non-object in laravel.log - without line of error.

After debug, I found problem. Missing data on accessing property.

First solution looks crary. It is checking is set for all child properties

if (isset($invoice->buyer) && isset($invoice->buyer->user) && isset($invoice->buyer->user->country)) {
    // Do sth
}

I tried to wrap above script into try-catch block. It was also not be worked.

via Chebli Mohamed