You have to set up your daughter with her own account on the website. I did it by entering my son's Fan ID, which is on the season ticket. Once you've done this, you should be given a seat next to yours for your daughter. At least, that's what happened to me earlier this morning. My seats are on the end of the small strip of red seats between the Ninian and the main red stand, very close to the away end. Not great, bit will have to do I guess.