rwockenf wrote:Does she need to use her card regularly to maintain an "active" status or because we are on the same account (even though there are different card numbers) will my activity count for both of us?
No. Minimum activity is per account -- not per card.
Vermonster wrote:Is it common for Amex to give different card numbers to AUs?
Not just common but standard. AmEx allows the account holder to restrict the amount of credit available to each AU and to track spend by user. This requires different card numbers.