welcome to HCM!
Your granddaughter seems to be having reactivation of CMV infection
specially since her immune system is low .
Once a person has had a CMV infection, the virus usually lies dormant or inactive in the body, but it can be reactivated. The virus is more likely to be reactivated — and cause serious illness — in people who have weakened immune systems due to illness.
you must visit your doctor and he will accordingly plan treatment for her.
hope this will help you!