with your siblings. Nikolas did save her life with his bone marrow because Laura, Lucky, Luke nor Bobby were a match, but the liver is a different elephant. Her best chance is someone who is a 100% match to reduce the chances of her body rejecting the liver down the line.
According to Gift of Life, half-siblings may be a half-match for a liver transplant, but they can't be a full match because they don't share both biological parents. This is because children only inherit 50% of their HLA from each parent, making each parent a half-match for their child.
However, a study found that recipients of genetically related donors had lower rates of acute cellular rejection than recipients of unrelated donors. The study also found that overall patient survival rates were similar between the two groups.