Maddie Brown of 'Sister Wives' Reveals Baby Daughter Has a Condition That Affects Bone Formation

'Sister Wives' star Maddie Brown shares an emotional post on Instagram, about her daughter's rare medical condition.

Since airing "Sister Wives" in 2010, fans have watched Maddie Brown grow from being a care-free and loving teenager to the dedicated mother of two she is today.

Maddie and her husband, Caleb Brush are the proud parents to Axel Brush and Evangalynn Kodi Brush. She often takes to social media to share her journey through motherhood; from adorable posts about her family to addressing mom-shamers attacking her parenting skills.

Recently, Maddie opened to her fans about her reality off camera. The mother of two revealed, her two-month-year-old daughter is suffering from a rare genetic disorder, which affects her bone formation.

In a lengthy Instagram post, Maddie begins by admitting that telling the public about their daughter's condition has been one of the hardest decisions she and Caleb have had to make.

She says her family hopes that by shedding light on the rare condition she can help other parents who are struggling with similar circumstances, Maddie explains:

"Our beautiful baby daughter Evie has been diagnosed with FATCO syndrome (basically the abbreviation for lots of intense Latin words?). It's a rare medical syndrome where bones in extremities do not fully develop."

FATCO affects a baby's bone formation while they are in utero. Maddie says the couple found out during her anatomy ultrasound at 26 weeks that there were some abnormalities. The doctors had informed them that she would be born with less than 10 fingers, she says:

"But when Evie was born, Caleb and I found out our precious little girl was missing more than just one finger."

"She was missing three fingers, a toe and her fibula. She also had a bowed tibia, a shortened forearm and some fusing in her fingers. It was at this point, the doctors diagnosed her with FATCO syndrome," she reveals.

Maddie tells PEOPLE, her family will have to wait while Evangalynn's body develops until she is one-year-old before they can consider medical interventions such as surgery and amputation.

She admits that she was hesitant to talk about Evangalynn's condition publicly for fear of people's jokes and cyberbullying.

She also adds that there have been fewer than 10 recorded cases and the cause is still not known. Maddie feels sharing this information also helps to remove any shame their daughter could feel if they continued to hide it because she wants her to be proud of the person she is.