It may be, if you make the assumption that the community she is in has such a service and that the bank in question is located in that community. But it is possible that neither assumption is accurate. For example, I went to high school in a pretty small community that even today does not have that kind of service because there is simply not nearly enough demand to make it worthwhile for someone to operate such a service.My reply earlier is SUPER accurate. The best, cheapest way is to have an ambulette or medi-van bring her if she's willing.
I agree with quincy that the type of account matters a lot. The most common sort of bank accounts done for kids are created under the state's Uniform Gift to Minors Act (UGMA) or Uniform Transfers to Minors Act (UTMA) and under both laws as soon as the kid reaches either the age of majority or age 21 (it varies by state) the kid automatically has sole control of the account — no action by the custodian is needed. So if it is a UTMA/UGMA account there should be no need for the mother to come to the bank at all.