Hiya Jennifer!
Welcome again to planDisney! I love that you want to bring your friend's teenager with you on your adventures in the Parks. It's really easy to add people to plan with people once they are on your Family & Friends List. You have a few choices for how to make it happen.
Have your friend share planning. If your friend, the parent, has created their own MyDisney account and has a managed account for their teen they can share all the plans with you. Either of you can head to the
Family & Friends List and select "
+ Add a Guest." Enter the needed information and make sure that the person you are connecting with accepts the invite. Once you share planning you will be able to connect to those that she manages. You may see them under the "Guests You May Know" section on the Add a Guest page.
Have the teen make their own MyDisney account and link to them. If the teen is
13 and older then they can create their account and connect with you in the way I mentioned above.
Make sure that you are all linked up well before the
Virtual Queue opens at 7 am and that everyone has a valid ticket for the Parks. You can prep a bit before by setting up your party as well so that when you click through the options at 7 am you will have your perfect party.
I hope this helps and you have a lovely time!
Happy Planning!
-Nimmy