Based on Dolly's age, this is likely what we call a viral papilloma caused by the papilloma virus. These regress on their own (typically within 1-5 months). These are contagious to other dogs so trying to limit exposure to other dogs is definitely something to consider. If a papilloma does not regress on its own or it becomes larger, there are various treatments that can be used such as oral Azithromycin (has been shown to reduce size or resolve papillomas within 10 days in some cases), freezing of the papillomas and surgical removal. For now, I would keep an eye on this and see if it regresses on its own. If at any time it increases in size or does not resolve, I would recommend having a veterinarian examine Dolly so that the most appropriate diagnostic and treatment recommendations can be made. I hope this helps guide you in the right direction. Please let me know if you have any other questions or concerns and I would be more than happy to help you further.