Fever possibly delaying resumption of chemo?

RSBNYC

My mother in law is a sixty-six-year-old woman who was diagnosed with a grade 4 glioblastoma last November. More than 95% of it was removed via surgery, the tumor is methylated, and she tolerated her initial treatment (six weeks of simultaneous radiation and temodar) well. Two weeks ago, she started her new cycle of temodar treatment (5 days in a row at double the original dose, followed, by 23 days off, repeated at least six times).

I'm writing because she has now been running a low fever (~100.0 degrees) off and on for the past two weeks. She caught a cold about a month ago, and as of last week she was still testing positive for rhinovirus. So, it could just be that her stressed out immune system is having trouble kicking the cold, but I'm concerned about this fever persisting for so long. Her team at Memorial Sloan Kettering (we live in NYC) says that if the fever doesn't resolve, she will be unable to start her next cycle of chemo pills, which is supposed to begin in 9 days. Her doctor seems to be adopting a "wait and see" approach to the fever, but I admit that makes me a bit nervous.

My question is, has anyone else experienced this while undergoing chemo? Any tips or recommendations for addressing it, or questions we should be asking her doctors? I am still somewhat new to the world of GBM caregiving and would appreciate any insight from people with more experience.