Hello and Welcome. Yes a mild fever is not uncommon and passing blood is also not uncommon, though you want to make sure that it is only minimal. I do hope your mom is on some medication and starting on her way to getting better. Once things get under control the fever, cramping and bleeding should all start to get better.
As far as diet, I keep to a low residue diet at all times. But when I am flaring or not feeling well I pare it down even further and do what I call my white food diet, mashed potato, rice, chicken, fish, eggs, pasta, custard, pudding, toast, you get the idea, anything you would eat when just getting over the flu. But diet is very individual. You can do a search using the search function in the upper right of the screen using the key words safe foods and crohn's and you will find all the most recent threads we have had discussing diet. Some of us have luck with one diet over another, it really is trial and error once things are under control.
CD 20 years officially, 30 unofficially. 3 resections '93, '95 '97
Managing with strict low residue diet, keeping symptoms to a minimum. All test show small amount of ulceration, still have occasional blockages. But still have a great time with my 2 daughters and husband!
Prednisone, 6MP,Prevacid, B12 shots, Bentyl, Xifaxan.....