FaceTime on multiple devices w/ 1 Apple ID

Question

I have 1 Apple ID, 5 Apple Devices, 2 new Itouches for the kids, but im getting an error saying their email addresses are already in use, which I know is NOT true.  is this a sync issue with Apple ID?

Answer 1

@dutra - Your suggestion worked like a charm. I have two options setup under my daughter's name in Facetime: Touch and iPAd. All I need to do is choose which I want to call. Easy-peasy.
@jeffreyfromorillia - This advice may be too late... But, register each device using your ID, as you should. Once this is complete do the following:
1 - Go to SETTINGS on device A
2 - Choose FACETIME
      - here you'll see your ID in the account field -- ignore it/leave it there.
     - below you'll see the email field, enter your daughter's email addy (you don't have to worry about the "+XXX"      unless she has more than once device because it applies only to the multiple device scenario)
     - IF you have used your email addy in the email field, click on Add Another Email and enter daughter's addy      here, then go back and choose your email addy and click remove
You are good to go. Repeat same steps for your stepdaughter's device.
If either girl has multiple devices you want to Facetime, follow steps 1 and 2, and in the email field click on Add Another Email and enter - [email protected] - then go back and delete orignal email entered. Do same for second device - [email protected], remembering to delete orginal email here, too.
On your device go to Facetime and edit contact - it prolly shows HOME / WORK / OTHER, click on it and choose CUSTOM, name it iPod, then enter the NEW email "[email protected]" and do same for second device, customizing the field to read iPad, or whatever you choose... Now you should have two options to choose from for contacting Girl 1. Repeat for Girl 2.
Hope this works for you, it worked out splendidly for me.
Cheers.