Represents the "Child" entry of the folder dictionary object.

It is defined as part of the PDF 1.7 Extension Level 3 specification.

It contains a FolderElement.

For definitive details see:.

Adobe Supplement to the ISO 32000, BaseVersion: 1.7, ExtensionLevel: 3; Table: 8.6c, page 32.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 159, page 451.

The Child entry references the first child folder of this folder. Following Child and then Next links traverses the entire subtree.