If your loved one has capacity to make decisions about their treatment and care, they need to give their doctor permission (either verbally or in writing) before they can talk to you about their health or prognosis.
However, if your loved one lacks capacity to make decisions, then the doctor must act in their best interests, which is very likely to include sharing relevant information with family and other people close to them.
If you’ve been appointed as your loved one’s attorney under a Lasting Power of Attorney for Health and Welfare (LPA), then you should be given any information you need to help you make decisions about their treatment and care.
If you don’t have power of attorney and you’re unable to get specific information about their health or prognosis, you. You’re also entitled to information and support for yourself as a carer from your local authority (the local council which is responsible for social care in your area).