How do you stop a family's members text messages from showing up on another family members computer (macbookpro) ?

10-11  Source: Network gathering  Views:0 

My daughter got a macbook pro and is receiving my son's text messages. We don't know how to avoid that. They share an apple itunes ID.
Hello kirkfromhopkinton,
After reviewing your post, I have located an article that can help in this situation. It contains a number of troubleshooting steps and helpful advice concerning Messages. You can sign out from Messages using the Preferences window:
Messages (Mavericks): iMessage pane of Accounts preferences
Thank you for contributing to Apple Support Communities.
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