Yes, it is possible but generally speaking canker sores are inside the mouth and HSV 1 manifests outside the mouth. However, with new infection, people can get HSV 1 inside the mouth. Is your HSV 1 oral or genital? Has a health care professional looked at those sores and swab tested them for herpes? It is good to remember that the common screening test for HSV 1 misses 1-2 infections out of every 10, so it isn’t great and she could be infected and not know it.