Suggestions for childdoc
The following packages have something in common with the package childdoc. The packages are ordered in decreasing similarity.
- subdocs: Multifile documents
 - combine: Bundle individual documents into a single document
 - newclude: Reimplemented \include system for LaTeX
 - minidocument: Creates miniature documents inside other LaTeX documents
 - docmute: Input files ignoring LaTeX preamble, etc.
 - includex: Extended \include
 - includernw: Include .Rnw inside .tex
 - subfiles: Individual typesetting of subfiles of a “main” document
 - standalone: Compile TeX pictures stand-alone or as part of a document
 - ltximg: Extract LaTeX environments into separate image files
 - was: A collection of small packages by Walter Schmidt
 - upgreek: Upright Greek letters
 - url: Verbatim with URL-sensitive line breaks
 - texments: Using the Pygments highlighter in LaTeX
 - nath: Natural mathematics notation
 - prosper: LaTeX class for high quality slides
 - subfloat: Sub-numbering for figures and tables
 - alnumsec: Alphanumeric section numbering
 - sudoku: Create sudoku grids
 - morehype: Hypertext tools for use with LaTeX
 - brclc: Support 16-bit (double) calculations in LaTeX
 - nicetext: Minimal markup for simple text (Wikipedia style) and documentation
 - handout: Create handout for auditors of a talk
 - balance: Balanced two-column mode
 - sciposter: Make posters of ISO A3 size and larger
 - bondgraph: Create bond graph figures in LaTeX documents
 - easyformat: Easily add boldface, italics and smallcaps
 - aguplus: Styles for American Geophysical Union
 - anysize: A simple package to set up document margins
 - aiaa: Typeset AIAA conference papers
 - anonchap: Make chapters be typeset like sections