"How can I keep their accounts in my portfolio view ....".
Assuming you're referring to Investing > Portfolio:
There are 18 "views" in the Quicken Portfolio: each one of those views has its own customizations.
To see your "separate" account in a view in the Portfolio:
- Select the view from the "Show" dropdown
- Click the Customize button
- Select the Accounts tab
- Make sure "Show hidden accounts is selected
- Make sure every account you want displayed is selected
["Separate" accounts are just a particular form of "Hidden" accounts. On the "Search Quicken Help" tab in Quicken Help, key "separate" in the search box and press Enter (or click iSeek). In the resulting list of topics, click "What are my account hiding options?"]