I just finished 12 rounds of chemo for stage 3c colon cancer.
I can relate to being scared about the battle he will have to fight to become cancer free. But he will have to put that behind him and engage the challenge ahead of him. I can't sugarcoat it to say it will be easy for him as it was not for me. But you will see people on this blog who did manage the side effects of chemo fairly well and worked. Everyone is different.
He needs to communicate with his oncologist at every chemo about what he experienced. I took notes every day about how I felt, if I went to the bathroom and if formed or loose, constipated, how many nausea or constipation meds I took, if I walked and for how long. My oncologist tweaked my meds till about my 6th chemo before we got the best outcome.
I took great comfort from my friends and family supporting me through email and facebook updates that I sent out! I am sure his family and friends will get behind him to provide whatever he needs as you have already done for him.
I congratulate you on taking this step for your brother-in-law. He is a very lucky person. I only found this site after chemo to see if I could find anyone else who has experienced the withdrawal from chemo that I am currently going through and how they dealt with it.