My sister have a blister on her lip?

last year, around this time of year too, my sister had these sores inside of her mouth. Now she is getting a blister-liket entity on her lip. Do you think this will turn into the problem she have last year? She works at the swimming pool as a lifeguard, so could it be because of that?My sister have a blister on her lip?
It is Herpes Simplex ~ cold sores.
It is a virus and once you hold it you have it surrounded by yuor body forever. You can use Herpecin to heal them.
Your body react to vitamin C and also to sunshine. Those things, amongst others, aggrivate it and it errupts.
too much sun will cause such blisters. it sounds resembling a cold sore, and is caused by the herpes virus that lives contained by our nerves if we had chicken pox as children. Different things can trigger an outbreak, resembling too much sun, too much emotional upset, too much caffiene, the document goes on and on.