When I make edits to file, TortoiseSVN will show an indication on the folder that file belongs to that there are changes pending to child items. AnkhSVN only shows (red tick) changes to a project when files are added/removed (because the actual content of the project file in this case has changed)
Can you make ankh give any indication at the project level that child items have been edited?
Unfortunately, no. Ankh only shows an indication on modified files, whereas TortoiseSVN can traverse folders recursively and mark those with changed files within them.
If you desperately need this feature, you can try out VisualSVN plugin. It tries to mimic TortoiseSVN behaviour as close as possible. In fact, it uses TSVN dialogs for operations such as Commit or Update, for instance. When you modify a file within a project, it highlights the file, the project this file belongs to, as well as the solution node in the Solution Explorer.
Unfortunately, it’s not free (US $49 per seat), but IMO it is worth its price.