01/03/2026
Today is National Rare Disease Day and we are honoring our sweet Emmett and the rare genetic mutation that shaped his entire journey.
Emmett had an EPHB4 gene mutation. EPHB4 plays an important role in how blood vessels and the circulatory system form and develop before birth. When this gene does not function properly, it can disrupt the normal development of veins, arteries, and the heart.
His mutation caused CM-AVM2, which stands for Capillary Malformation–Arteriovenous Malformation type 2. This condition affects the vascular system and can cause abnormal connections between arteries and veins. These abnormal connections are called arteriovenous malformations. They can change the way blood flows through the body and put extra strain on the heart.
Emmett also had severe Ebstein’s anomaly with pulmonary atresia. Ebstein’s anomaly is a rare congenital heart defect that affects the tricuspid valve. In this condition, the valve is malformed and sits lower than normal inside the right side of the heart. This can cause the right side of the heart to be enlarged and function poorly. Pulmonary atresia means the pulmonary valve, which allows blood to flow from the heart to the lungs, did not form correctly. Because of this, blood could not flow normally to his lungs to pick up oxygen. Both of these conditions together made his heart anatomy extremely complex and very fragile.
On top of that, Emmett had Abernethy malformation. This is a rare vascular condition where the portal vein, which normally carries blood from the intestines to the liver, does not connect to the liver the way it should. Instead, the blood bypasses the liver and drains directly into the systemic circulation. The liver plays a critical role in filtering toxins and supporting overall metabolism, so this abnormal blood flow can affect many systems in the body.
Each of these diagnoses on their own is rare. Together, they made Emmett’s anatomy very complicated and incredibly high risk. There was no clear roadmap. No large studies. No easy answers. Just a tiny baby fighting against odds most people will never have to imagine.
Rare diseases affect millions of families, yet each individual condition may impact only a small number of people. When you are the parent of a child with a rare diagnosis, you quickly learn how isolating it can feel. You also learn how strong your child truly is. Stronger than they should ever have to be.
Emmett lived his entire life in the hospital. He endured more procedures, surgeries, and challenges than most adults will in a lifetime. And still, he showed us what courage looks like in its purest form.
Today we honor him. We share his name and story. We raise awareness for EPHB4 mutations, CM-AVM2, Ebstein’s anomaly, pulmonary atresia, and Abernethy malformation. We stand with every family navigating a diagnosis that most of the world has never heard of. Rare doesn’t mean alone.❤️🩹🐌