Warts do tend to come back rather frequently, so you may find yourself starting your
treatment all over again, or trying different treatments over time. Becasue of warts' persistance many home remedies have also been thought of over centuries and eons. Although these have not been proven scientifically, a home remedy may also help you. In this case I recommend discussing which these remedies with your grandmother. Warts are frustrating little viruses so you should consider all options.