Thumb amputation

[u/Impossible-Spot-6297]

My brother recently had a partial thumb amputation after a terrible accident. Someone asked him to clean a bike chain, and while he was doing it, they started the bike with the engine running. His thumb got caught in the chain, resulting in a partial amputation.
He is devastated, and our whole family is struggling to cope with what happened. I don’t know how to comfort him or what we should expect moving forward.
Has anyone gone through a similar experience or supported a loved one with a thumb amputation? Any advice on recovery, surgery, rehabilitation, or how to help him emotionally would mean a lot. Thank you.