Munchausen's Syndrome is a psychological disorder where someone feels the need to fake an illness. This is often to the point of forcing symptoms upon themselves. This behavior is however not driven by the desire of any tangible benefits. The goal is simply to be the center of attention.
A significantly more twisted variant would be Munchausen's Syndrome by Proxy. In this, the individual isn't forcing an illness upon themselves, but upon another (or other) human being(s). This includes a wide variety of cases. One example being a mother that suffocated her children after two of her children died (one being a still born and the other dying whislt still in the hospital). After those deaths, all future children of hers all suffered from "heart attacks" within a few months of birth. Doctors just assumed that her genetic were bad considering how the first death occurred within the hospital. Thus 6 more deaths came and went. That was until she adopted a child which also soon died a similar "heart attack" death. Obviously very suspicious.
After her next child died, they took it for a full autopsy which revealed that the child had been suffocated. She stated that she killed her children because she dreaded the idea of them dying and wanted to just get it over with.
[It's extremely scary how many different results show up when you search for "mother suffocates 8 children." If that's such a "common" occurrence, how insanely high must the numbers be for just one or two children.]
Munchausen's Syndrome by Proxy doesn't need to involve a death, but it can most certainly be extremely torturous for the targeted individual.