Chase was born prematurely and was legally blind. At one year old the doctors did an MRI, expecting to find mild cerebral palsy. Instead, they discovered he was missing his cerebellum - which controls motor skills, balance and emotions.
That's when the medical doctors said, "That's impossible. He has the MRI of a vegetable."
"There are some very bright, specialized people across the country and in Europe that have put their minds to this dilemma and are continuing to do so, and we haven't come up with an answer," Dr. Adre du Plessis, chief of Fetal and Transitional Medicine at Children's National Medical Center in Washington, D.C., told Fox News affiliate WGRZ.
"So it is a mystery."
Chase also is missing his pons, the part of the brain stem that controls basic functions, such as sleeping and breathing. There is only fluid where the cerebellum and pons should be.