E velyn was an “easy baby.” We had all kinds of experience with difficult babies after our first two, but Evelyn was so different. She loved naptime and bedtime so much I could simply lay her down awake and say goodnight, and she never fought to stay awake or cried. In fact, as soon as she was old enough to smile, she would smile the biggest, toothless grin when I’d say it was bedtime.

Evelyn was small and grew slowly, but she was a great nurser and a happy baby. She seemed to be in no rush to roll over or bear weight, and four and then five and then six months came and went without her rolling. But the pediatrician said I shouldn’t worry; she was probably laid back because she had older siblings to tote her around.

When she was around four months old, the pediatrician noticed she still had a head lag (she didn’t lift her head at the neck when pulled into a sitting position), and that she favored looking to one side. I took her for a physical therapy evaluation and found she had torticollis, a shortening of the muscle on one side of the neck that makes it hard to look the other direction. We spent the next six months in bi-weekly PT sessions, and while the torticollis cleared up nicely her muscle strength still seemed on the low end of normal.

Evie hit all her milestones, but she hit them each late: rolling at seven months, sitting at ten months, pulling up to stand at a year. At her 15 month well check, she had fallen off the chart for weight and the doctor mentioned the phrase “failure to thrive.” She recommended we do a bit of blood work, see a few specialists to rule out any issues, but really no one was concerned. Evelyn was happy, eating well, sleeping well, interacting with her siblings. She was a sweet baby.

By this time, I knew something was different. She wasn't just laid back or just a happy baby. So I went down a path that parents of kids with a diagnosis understand all too well: I decided to pursue a diagnosis, and find answers, no matter what.

The next two years were a landslide of specialist appointments, blood draws, tests. She was evaluated by an endocrinologist, neurologist, developmental pediatrician, audiologist, optometrist. She had a bone-age X-ray; blood tests for celiac disease, growth hormone levels, carnitine, a chromosome analysis, a microarray.

The results were always the same. Every health test was normal; she was healthy. But every developmental assessment was concerning. She was delayed in gross and fine motor, delayed in expressive speech, delayed cognitively. Her muscle tone was low. Her pinkie fingers were slightly bent (clinodactyly). She was diagnosed at 18 months with apraxia of speech (a disorder specialists say shouldn’t be diagnosed until 3 years old, but Evelyn presented so obviously and so early it was clear).

Finally at 19 months Evelyn had a brain MRI, and was diagnosed with Dandy-Walker Variant based on a very small cerebellum and a fluid filled pouch at the back of her brain where her cerebellum should have been.

But I'm a researcher, and it wasn't long before I knew Dandy-Walker Variant is a sort of throwaway diagnosis that doesn’t tell you anything. Dandy-Walker is a syndrome with pretty clear criteria for diagnosis, but the Variant designation is out-of-date and used whenever the cerebellum is affected and doctors don’t know why.

I knew that wasn’t it. There was more to her story.

Armed with the Dandy-Walker diagnosis, her geneticist was able to present the case to insurance to cover a brain malformation genetic panel, but after waiting for results for weeks, it only showed a few variants of unknown significance.

He said we could just take a wait-and-see approach (wait, I guess, to see if she had other symptoms that would indicate a differential diagnosis).

Or. We could do Whole Exome Sequencing. It's kind of the grandfather of genetic tests, testing the most genes at once for a standard commercially available genetic test.

He said we probably wouldn’t find anything. But we might.

We had blood drawn from me, my husband and Evelyn in October 2016. Then we waited.

Three months later, the results were conclusive: One faulty allele from me, and one from her father, and bam: Evelyn has POLG-related mitochondrial depletion syndrome. An energy production disease. Typically fatal in childhood.

I hate this journey-to-diagnosis story because it makes her life about this one moment. But really, her story has just begun. Evelyn is defying mito, and I can’t wait to see what comes next.