You'll have to ask at a check in counter as you can't get thru security without a pass or a ticket. You could tell them she needs extra assistance and you need to be there to help. There's always the option of buying a fully refundable ticket if you can't get a pass, but it may take a while for the refund to show up on your credit card. What airline is she flying? The Air Tran
agents at the counter near the MARTA entrance have always been very helpful when I'm dropping off a 95 yr. old who needs whelchair assistance.