protected function isActualRelationships(string $relation): bool
    {
        return array_key_exists($relation, $this->relationships)
            && count($this->relationships[$relation]) > 0;
    }
protected function isActualRelationships(string $relation): bool
    {
        return array_key_exists($relation, $this->relationships)
            && count($this->relationships[$relation]) > 0;
    }
protected function isActualRelationships ( string $ relation ) : bool { return array_key_exists ( $ relation , $ this -> relationships ) && count ( $ this -> relationships [ $ relation ] ) > 0 ; }
Check the existence of an actual relationship.

@param string $relation

@return bool
Check the existence of an actual relationship .