This study investigates Biliary Atresia, a liver condition that affects children. Biliary Atresia is a condition where the bile ducts inside or outside the liver do not have normal openings, causing bile to be trapped and leading to liver damage. The purpose of this study is to collect medical information to better understand the natural history and causes of this condition.

Participants will be involved in procedures to collect medical data. These procedures might include regular health check-ups and tests to monitor liver function and overall health. The study aims to gather detailed information that can help researchers learn more about how Biliary Atresia develops and progresses over time.

• Who can participate: Children with a confirmed diagnosis of Biliary Atresia who are at least one year old can participate. Participants must either have their native liver or a confirmed liver transplant, and consent must be provided by a parent, guardian, or the participant when appropriate.
• Study details: Participants will be required to attend scheduled visits and provide medical information. This study does not involve any investigational medication or placebo.