Hi Kim,
so sorry for you and your mom.
My husband who is 43 is 5 days away from finishing his radiation.
hair loss depends upon the area of the brain the docs are hitting. My husband used to have beeeutiful hair(he is a musician and a rock and roller :) )
he has lost 70% of his hair. His hair started falling out 10 days into radiation.... we had a really great and loving evening shaving his head.
Ask the radio-oncologist where he is targeting the radiology therapy..then you will know where your mom will lose her hair.
My husband has done fabulously with the radiation and chemo...he is just now getting tired.
I hpoe your mom does well...
take care, Eve