Q: sub accounts possible in itunes?

Hello RenegadeK,

It sounds like your child and you share the same computer but have your own iOS devices.  I can definitely understand the desire to keep your information separate, and there are a few things you would need to look at. 

First, if you are syncing content with iTunes, I recommend reviewing the following article for information about syncing content to multiple devices using iTunes.  It will provide you a few options for syncing so that you can pick the method that would work best for you:

How to use multiple iPhone, iPad, or iPod devices with one computer

http://support.apple.com/kb/HT1495

The next thing to consider is having separate Apple IDs.  This will allow you to have separate accounts for services like iCloud, Messages, FaceTime, and the iTunes Store.  I recommend reviewing the following articles for more information about creating and using an Apple ID:

iTunes: How to set up an Apple ID within iTunes

http://support.apple.com/kb/HT2731

Using your Apple ID for Apple services

http://support.apple.com/kb/HT4895

Frequently asked questions about Apple ID

http://support.apple.com/kb/HT5622

Additionally, your Apple ID may be signed into your child's Messages settings.  You can check the settings for Messages and FaceTime on your child's device to sign out of your Apple ID:

On iOS devices, find out which addresses are enabled with FaceTime and iMessage by tapping:

 

• Settings > Messages > Send & Receive > You can be reached by iMessage at:
• Settings > FaceTime > You can be reached by FaceTime at:

iOS and OS X: Link your phone number and Apple ID for use with FaceTime and iMessage

http://support.apple.com/kb/HT5538

Thank you for using Apple Support Communities.

Best,

Sheila M.