Hello DawnSiler
See my other reply concerning the purchase of a Swiss Half Fare Card in advance:
https://community.sbb-tickets.cc/d/24914-unable-to-purchase-a-swiss-half-fare-card
She could purchase the Swiss Half Fare Card by herself just before arrival; or at the SBB Travel Center at the airport. There, the SHFC is issued as a paper ticket, though.
You cannot use one and the same e-mail address twice, for different accounts. You would have to use another e-mail address and change it to hers at a later stage.
Kind regards,
Roland
Kind regards,
Roland