7 year old with calcium deposits on the brain?

My neice is 7 years old and about 6 months ago had an unexplained fever for about a week. Bloodwork then was all normal. Then about a month ago she started having real bad headaches. Migraine like headaches. My SIL took her to the doctor and they did a CT Scan. They told my SIL she had calcium deposits and they are wanting to do a MRI and her to see a pediatric brain specialist. I can't find any information about calcium deposits on the brain on the web. Does anyone have any legitimate information?