Thanks for the query,
She might have developed a rubella infection,
Dont worry its a mild condition she will soon recover.
Apply a mild steroid
lotion like desonide
Also take an antihistamine syrup like cetrizine
This will give you some relief.
The disease is self limiting
Please meet a dermatologist
for exact diagnosis.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.