This property represents the "Kids" entry of the number tree node dictionary object.

It is defined as part of the PDF 1.0 specification.

An Array containing child NumberTreeNodeElements which may be intermediate or leaf nodes.

This entry is always null in leaf nodes. In intermediate nodes it must always be non-null.

In the root node either this entry or the EntryNums entry should be non-null. But not both.

For definitive details see:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 37, page 91.