Both brothers were perfectly capable of taking a lethal dose of whatever pills they could get their hands on without dragging a doctor into it.
Why did somebody else have to do the deed? They turned suicide into murder.
If they killed a few people first, they would have been spared.
There are doctors lined up all over Europe waiting for such jobs. Good reason to not get sick or hurt in Europe.
You have to wonder what kind of encouragement they got from the euthenasia crowd.
I prefer to think of it as friends aiding friends in an honorable act.