t was supposed to be ordinary family life — five children, birthdays, school milestones, and summer vacations. But for Erin and Benjamin Mading, that ordinary life turned into something profoundly different when a rare genetic condition called Constitutional Mismatch Repair Deficiency (CMMRD) began claiming the lives of their children one by one.
CMMRD is an extremely rare inherited cancer-predisposition syndrome. It occurs when a child inherits two defective copies of the same mismatch-repair gene — one from each parent — leading to a dramatically elevated risk of early-onset cancers such as brain tumors and other malignancies in childhood.
A Trio of Heartbreak: Cody, Averi & Isabella
The first clue that something was deeply wrong came with their son Cody. He was a young man with tenacity and heart — but at age 16, he was diagnosed with a rare brain tumor. Despite everything Cody fought for, he died at just 17 years old.
A few years later, their daughter Averi was diagnosed with her own devastating battle. After precancerous polyps were discovered during a routine check, she faced aggressive cancer and passed away at 17 on Christmas Eve.
And then came Isabella — Bell, the youngest of the three affected siblings. Full of life, curiosity, and dreams of becoming a nurse someday, Bell was diagnosed with a brain tumor linked to CMMRD at just 7 years old. She fought bravely, living every day with joy, silliness, and kindness — the “social butterfly” her mom described her as. Sadly, Bell died at 10 years old, surrounded by the love of her family.
Erin has said that remembering her children brings moments of joy and unbearable sorrow — “Everywhere I go, there are reminders of her.” But she also finds comfort in imagining that all three siblings are together now.
Understanding What Happened: CMMRD Explained
The Medings didn’t initially know the cause of their children’s illnesses. It was only after Cody’s diagnosis that doctors dug deeper into the genetics behind this pattern of cancers in such young individuals.
CMMRD happens when both parents carry a mutation in the same mismatch-repair gene — often MLH1, MSH2, MSH6, or PMS2 — and each parent passes that faulty gene to their child. Because these genes normally help repair DNA errors that occur when cells divide, having two defective copies means cells accumulate mutations quickly, which can lead to early-onset cancers.
Unlike Lynch syndrome — which is caused by a single defective mismatch-repair gene and typically leads to adult cancers — CMMRD dramatically increases cancer risk in childhood, especially brain tumors.
Doctors estimate that when both parents are carriers of the same mutation, each child has a 1-in-4 chance of inheriting CMMRD.
Life, Joy & Courage Amid the Pain
Despite the devastating pattern of illness, the siblings lived full lives in the time they had. Bell’s mom fondly recalled how she “lived life to the fullest”, especially in her final year, showing a spirit that impacted everyone around her.
Even though tragically all three of the Mading children who had CMMRD passed away, their living siblings — Kylie and Olivia — each faced their own decisions about genetic testing. One has tested negative for the familial mutation, and the other has opted not to be tested — a choice their mother supports.
Turning Grief Into Purpose
Erin Mading didn’t allow her grief to remain private. She has worked to raise awareness about CMMRD, pushing for greater understanding of hereditary cancer syndromes and better support for affected families.
She also helped create a CMMRD awareness ribbon with a cheetah-print design — a symbol meant to shine a light on this incredibly rare condition and support other families on similar journeys.
Erin has spoken publicly about her children’s lives and struggles, stressing the importance of genetic counseling, family testing, and early detection — tools that might help prevent other families from enduring the same tragic losses.
Remembering the Madings
The story of Cody, Averi, and Isabella — and of their family’s tireless commitment to understanding CMMRD — is both heartbreaking and inspiring. It’s a reminder that rare diseases can affect ordinary families in extraordinary ways, and that sometimes, even when science can’t yet cure a condition, education and advocacy can be powerful forces for change.
Their legacy lives on in the awareness their story continues to raise and in the hearts of everyone who hears it.
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