Sister Wives star Maddie Brown Brush’s infant daughter Evangalynn was born with an extremely rare genetic disorder, FATCO syndrome, which affects the formation of the bones in the uterus. Her future is still uncertain to her parents, who have to wait for a year to know her course of treatment.

It all started when she went for a regular ultrasound in her 28th-week of pregnancy. The doctor seemed to take more time than usual and that made the reality star apprehensive about the baby growing inside her. Brown told People in this week’s issue, on newsstands Friday, “It usually takes about 45 minutes, but the doctor just kept looking and looking. I was stressing out the whole time.”

After checking for two hours, the doctor finally asked her to meet in his office, where he explained that he couldn't find all ten fingers on the baby. She was diagnosed with oligodactyly, a congenital anomaly defined as the presence of fewer than five fingers on a hand. 23-year-old Maddie recalls, “There were lots of emotions, but I was also relieved because there could have been a whole lot more wrong.”

However, when the couple welcomed their baby on August 20, the newborn had a missing thumb, a missing toe, one of her legs did not have calf bone, and a bowed shinbone. Two of her fingers were also fused.

Brown Brush, who also has a 2-year-old son, Axel James, adds, “I was just sitting there trying to comprehend what’s going on, having just had a baby as they are bringing in all these specialists. I was freaking out.” Due to undetected causes, Evangalynn was detected with tibial campomelia, fibular aplasia, and oligosyndactyly (FATCO) syndrome, an extremely intermittent genetic disorder that affects bone formation in utero. And since it’s a rare disease, doctors cannot predict much about her future progress. They will have to give her body more time to develop and wait till she turns one to decide the course of treatment, which can include surgery or amputation.

Brown Bush has been initially hesitant to speak about her daughter, and she accepts that it's "abnormal" and has caught them off-guard. She also added, “But, I want her to grow up and feel proud about who she is. If I’m hiding this to protect her, is it really helpful?”

So, the mother of two wrote on Instagram, “Our beautiful baby daughter Evie has been diagnosed with FATCO syndrome (basically the abbreviation for lots of intense Latin words).” She posted it with an adorable photo of her baby girl. The precious photograph of the infant in a yellow bow and diaper also made her physical abnormalities visible.

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Other than her bone defects, the child is healthy, and the mother says, "We want Evie to always feel pride in who she is, and all that God gave her!'. We hope she enjoys a healthy and long life.