Eloquent Relationship Three Tables

I think your looking for an hasManyThrough relation.

You can simple add an method on your Author model to fetch an authors comments that goes trough your Post model. Add this your Author model:

public function comments()
{
    return $this->hasManyThrough(
        'App\Comment',
        'App\Post',
        'author_id', // Foreign key on post table...
        'post_id', // Foreign key on comments table...
    );
}

Now you can check if there are comments where comment column is okay by accessing it like this:

$author             = Author::find(1);
$author_comments    = $author->comments()->where('comment',  'okay')->get();

You can change the where clause however you like.

I recommend you to read the information behind this link to understand how this exactly work: laravel.com/docs/5.6/eloquent-relationships#has-many-through

First, thank you for your reply.

This works if $author returns a single record.

but if $author returns more than one record, it doesn't work.

I have this:

$author = Author::where('name', 'like', '%john%');

am i missing something?