// When I fetch all records from a table specifying a foreign key I get results returned
return $this->slide->where('foreign_key', '=', $foreign_key)
	->get()
	->all();

// But when I try fetch a specific model using the id and foreign key I get an empty array
return $this->slide->where('id', '=', $id)
	->where('foreign_key', '=', $foreign_key)
	->get();

// This is what's returned when I do a dd() of the query result
object(Illuminate\Database\Eloquent\Collection)#505 (1) { ["items":protected]=> array(0) { } }