Why did Hitler spare his mother's Doctor ?

So Mother of Hitler had doctor and he was a Jew, he treated her for cancer but she still ended up dying and later Hitler spared him, why would he spare him, wouldn't he assume that the reason his mother died is because he was a Jew so by his racist logic he wasn't as good of a doctor wich is why his mother died, cuz an Aryan would have been able to treat her according to the Nazi logic since they are "Superior" (I know they aren't).