Where I live you can totally disinherit blood relatives, unless doing so would somehow go against the country's constitution. (It's a long document and has a lot of stipulations about dignity, human rights, children's rights, etc.) It would be too convoluted to explain all of the possible exceptions to disinheriting someone, so I'll just say that common sense usually applies to will disputes. Similarly to nintii's country, in mine you can place everything you own in a trust fund, and then nobody will be able to touch it. Courts are much more formal, literal and strict about company/business/commercial law than they are about personal/private/constitutional law, so if I were to place my belongings in a trust fund and I then died, I doubt family members could do a thing about being disinherited.