How Far Does Patient Confidentiality Extend?

These are difficult times for medics. There is news that a woman in the UK is to sue a hospital for not informing her that her father had the fatal, neurodegenerative disease of Huntington's chorea (https://www.theguardian.com/science/2018/nov/25/woman-inherited-fatal-illness-sue-doctors-groundbreaking-case-huntingtons). The hospital doctors presumably did not formally inform the immediate family of the man because of patient confidentiality (but they might have suggested that the man should inform his children as they would have a 50% chance of inheriting this condition which currently has no cure). The woman claims that, had she been informed, she would have had an abortion rather than giving birth to her daughter 8 years ago (as the woman has inherited the condition, also giving her daughter a 50% chance of developing the disease). This is a difficult one (and not, in my view, one for the legal eagles). The situation seems straight forward as described but the availability of gene testing techniques is reportedly revealing odd family secrets and misconceptions (no pun intended). What if the father had not actually conceived his 'daughter' and, because she was informed of his condition, she had an entirely unnecessary abortion? Would hospital be liable for this? I think that medical ethics needs to get on the case and give some clear guidance.