Why are messages being sent to my sister's phone? help!
My sister's iPhone is on my account. She's getting my messages that I send to people she doesn't even know! How do I prevent this?
iPhone 5, iOS 7.1
RECEIVING MESSAGES INTENDED FOR OTHER DEVICES
This occurs if you are sharing the same Apple ID for imessages.
If you are receiving imessages intended for other devices you can fix this by going to Settings>Messages>Send & Receive and do one of the following:
Uncheck the email address shown under "You can be reached by iMessage at" on both devices if they are iPhones; or
On one of the devices go to Settings>Messages>Send & Receive, tap the Apple ID, sign out, then sign in with a different Apple ID. Note: you can continue to share an Apple ID for the iTunes & App store for purchasing if you wish; it does not need to be the same as the ID you use for iMessage, FaceTime, iCloud and other services.
To prevent merging of your calendars and contacts when syncing calendars and contacts if you are using the same Apple ID for the iCloud account, be sure to set up separate iCloud accounts on each phone with separated IDs. Remember that if you change your ID in iTunes & App store, that apps and other purchased content is forever linked to the ID that was used to download the apps and the apps can only be updated with the ID that was originally used to download them. To download content purchased previously downloaded with a particular ID then that ID needs to be used to download past purchases. If you want all apps to be connected with the same ID you need to delete those apps downloaded with the old ID and download them again with your current and if the apps in question were paid apps then you need to pay again.
Read http://macmost.com/setting-up-multiple-ios-devices-for-messages-and-facetime.htm l
If you wish to share an Apple ID with family members then read: http://www.macstories.net/stories/ios-5-icloud-tips-sharing-an-apple-id-with-you r-family/