Solution:

You start it by creating a scope inside your Notification. The following code will help you understand. 

After this write the following code:

Or if you have other relation to eager:

So it's up to you how to organize an modify the code to suit your needs

Update:

The $with always depends on model columns. Therefore, if you are not selecting for exmaple subscription_id and photo_file_id, automatic relation loading will not work.

Would you give it a try

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