@aam9422 My sincerest empathy to your brother for having gone through the SCT process and having it fail. Unfortunately it happens and requires another attempt.

In your brother’s case having a child be the donor gives a 50% match of his DNA.
50% of the DNA is your brother’s own DNA, so that’s a perfect match, but the remaining 50% is from his wife and might totally miss the mark. Any time a completely foreign DNA is introduced into a body you can imagine there will be some complications. In your brother’s case it is rejection.

Being a sibling, you could potentially be a closer match to your brother if you have the same parents. But again, there are other factors in determining which donor DNA will have the desired outcome to preventing the disease from returning. The search for a donor may also come from a national/international donor registry. An even more suitable match might be found for him from an absolute stranger. So don’t despair if you are not a match. Determining a donor is an extremely complex undertaking.

The DNA needs to match but not too closely. If it does then it may not have the desired effect of creating an internal war against any re-emerging cancer cells. Too foreign, then it can be rejected or create other serious issues. So the transplant team will be taking extreme caution in procuring cells for your brother. It would be great if you’re that match as it would certainly speed up the process of getting that second SCT underway quickly! Good luck to both of you!!

Your brother must be physically drained and tired. How is he handling all of this emotionally? Is he allowed to have visitors? Having all of this while under Covid protocol is extra taxing on everyone. You’re both in my thoughts as you wait this out…. Hugs, Lori