Array
(
    [1699] => Array
        (
            [parent_category_id] => 1699
            [parent_category] => Array
                (
                    [id] => 1699
                    [slug] => languages
                    [name] => Languages
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Chinese
                            [slug] => chinese
                            [id] => 1708
                        )

                )

        )

    [1723] => Array
        (
            [parent_category_id] => 1723
            [parent_category] => Array
                (
                    [id] => 1723
                    [slug] => math
                    [name] => Math
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Algebra 1
                            [slug] => algebra-1
                            [id] => 1725
                        )

                    [1] => Array
                        (
                            [name] => Elementary Math
                            [slug] => elementary-math
                            [id] => 1743
                        )

                    [2] => Array
                        (
                            [name] => SAT Math
                            [slug] => sat-math
                            [id] => 1740
                        )

                )

        )

)