Grok 3 beta:
The surgeon is the cousin's father. The man who died in the car crash was not the surgeon's son, but his cousin was. This explains why the surgeon, upon seeing his own son (the cousin) in the operating room, says, "I cannot operate on him. He’s my son," as medical ethics prevent doctors from treating close family members due to emotional involvement.
Also bad, why does it think the surgeon is the father if it could also be the mother?
It's not bad, because it's one of the valid solutions to that riddle.
How often do you expect to have every possible answer to your question?
It is bad, because it’s one possible solution, but it’s phrased like it’s the single possible solution.