EloquentFilter\ModelFilter::related PHP Method

    public function related($relation, $column, $operator = null, $value = null, $boolean = 'and')
    {
        if ($column instanceof \Closure) {
            $this->addRelated($relation, $column);
        } else {
            // If there is no value it is a where = ? query and we set the appropriate params
            if ($value === null) {
                $value = $operator;
                $operator = '=';
            }
            $this->addRelated($relation, function ($query) use($column, $operator, $value, $boolean) {
                return $query->where($column, $operator, $value, $boolean);
            });
        }
    }