public function getChilds($withOwnRole = false)
    {
        $id         = $this->id;
        $roles      = $this->withTrashed()->orderby('parent_id')->get()->toArray();
        $lowerRoles = $this->getLowerRoles($roles, $id);
        return ($withOwnRole) ? array_merge([$this->id], $lowerRoles) : $lowerRoles;
    }