Table of contents and merged projects

Hi all,

How do people manage merged projects when you need to include topics from sibling projects in the table of contents?

For example:

ProjectA :

Searching for a widget

Searching for a note

Searching for a reminder

Creating a note

Updating a note

Deleting a note

Creating a reminder

Updatng a reminder

Deleting a reminder

ProjectB: All about widgets

ProjectC: All about doohickeys

As part of the process of creating a widget a number of tasks need to be completed, so the table of contents is structured to cover the relevant tasks

ProjectA ToC

- About notes

-- Creating a note

-- Deleting a note

- About reminders

-- Creating a note

-- Deleting a note

etc

ProjectB ToC

- Configuring a widget

-- Creating a widget

-- Creating a note

-- Creating a reminder

- Updating a widget 

etc

ProjectC ToC

- Configuring a doohickey

-- Creating a doohickey

-- Creating a note

-- Creating a reminder

etc

How do you go about adding the note and reminder pages into the table of contents for ProjectB and ProjectC? Or do you advise avoiding this and if so what strategies do you use instead?

Thanks,

Amber