1- To remove financial incentives for destroying your sibling, a child should be able to decide if he died before his parent his (future) heritage (at death of the parents) goes to someone else (e.g. a charity) instead of his sibling (I even suggest that the this happens by default law. For myself a very rare event caused that I found out my brother annoyances were on purpose)He depraved me from sleep for a long time by his annoyances. Later (on a rare luck) I found out all excuses for these annoyances was fake.
When he found a vulnerability about me he would stuck with it after that. (but with excuse).On another period several times he destroyed my mattresses. When I wasn't in room. I was thinking the problem is my body or bad quality of mattresses
Or in last years he (or his devil fiancé) used carcinogen (or just antisleep drug) in my food. when I found I have cancer it was too late to proof anything
2- Additional suggestion: There should be even a fine on surviving sibling's heritage or even getting confiscating sibling heritage (what communist suggests), if other sibling died before certain age.
Sometimes the incentive for destroying you is something more than greed, like my case that he wanted to bring me down to his level because he wanted to pass his young ages without being forced to go university by my parents. He made me his shield. Or sometimes he want to destroy you because you have occupied sofa in the morning.
Note that It applies only if death not caused by something that there is no way that sibling has effect on it, like death in war.
This law and the previous one can also be provided as an option. Some one can opt in that if he died at certain age (determined by law), this happens for my siblings' heritage
Note 1: The reason nobody suggested this before me is that, victims of this situation, are died before they have chance to think or talk. A rare specific situation in my country given me this chance before death
Note 2: Actually my brother is dumb in math and IQ test but an evil bully. On the other hand I was accepted in math Olympic. I say this for those who think the current situation is good for eugenics