Array
(
    [1872] => Array
        (
            [parent_category_id] => 1872
            [parent_category] => Array
                (
                    [id] => 1872
                    [slug] => health-medical
                    [name] => Health and Medical
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => USMLE
                            [slug] => usmle
                            [id] => 1878
                        )

                )

        )

    [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] => Geometry
                            [slug] => geometry
                            [id] => 1727
                        )

                    [2] => Array
                        (
                            [name] => Prealgebra
                            [slug] => prealgebra
                            [id] => 1724
                        )

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

                )

        )

    [1915] => Array
        (
            [parent_category_id] => 1915
            [parent_category] => Array
                (
                    [id] => 1915
                    [slug] => miscellaneous
                    [name] => Miscellaneous / Other
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Fitness
                            [slug] => fitness
                            [id] => 1917
                        )

                )

        )

    [1744] => Array
        (
            [parent_category_id] => 1744
            [parent_category] => Array
                (
                    [id] => 1744
                    [slug] => science
                    [name] => Science
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => Biochemistry
                            [slug] => biochemistry
                            [id] => 1751
                        )

                    [1] => Array
                        (
                            [name] => Biology
                            [slug] => biology
                            [id] => 1746
                        )

                    [2] => Array
                        (
                            [name] => Chemistry
                            [slug] => chemistry
                            [id] => 1747
                        )

                    [3] => Array
                        (
                            [name] => Genetics
                            [slug] => genetics
                            [id] => 1753
                        )

                    [4] => Array
                        (
                            [name] => Organic Chemistry
                            [slug] => organic-chemistry
                            [id] => 1754
                        )

                    [5] => Array
                        (
                            [name] => Physiology
                            [slug] => physiology
                            [id] => 1750
                        )

                )

        )

    [1856] => Array
        (
            [parent_category_id] => 1856
            [parent_category] => Array
                (
                    [id] => 1856
                    [slug] => test-prep-exams
                    [name] => Test Prep and Exams
                )

            [subcategories] => Array
                (
                    [0] => Array
                        (
                            [name] => ACT Science
                            [slug] => act-science
                            [id] => 1870
                        )

                    [1] => Array
                        (
                            [name] => MCAT
                            [slug] => mcat
                            [id] => 1865
                        )

                )

        )

)