She was curled up on the floor beside my bed, playing with the dog so she didn’t have to look me in the eye when she asked. “You and Daddy have depression. Am I going to have depression, too?”

My daughter is 11, all hormones and aching joints. Her body and her whole outlook on life is in flux. She’s begun to express fears of things that until recently she seemed not to know existed. Death. Terrorism. Climate change. A discussion of the polar ice caps ended in tears. Talk of the presidency sometimes sends her to her room, the door slamming behind her. Are they signs of depression, I asked my psychiatrist, or signs of growing up?

What I wanted to ask was “Have I doomed my child to repeating my life? Was I selfish to have a child, knowing I could pass this along? Is it okay to have kids, knowing the risk?”

Genetic testing before pregnancy has become increasingly popular. For less than $200, companies such as 23andMe offer at least a broad-brush look at DNA to guide would-be parents as they debate conception vs. adoption. Some fertility doctors offer ­pre-implantation genetic testing during the in vitro fertilization process, screening the lab embryo for diseases and genetic abnormalities so parents can decide whether to proceed with implantation and pregnancy.

[My mother was depressed most of my life. Will that happen to me, too?]

But what about conditions that don’t show up on genetic tests at all? Conditions that adults carry around like an albatross, heavy on their shoulders?

An estimated 40 to 50 percent of major depression appears linked to heredity. My daughter has a double whammy: Both of her parents have battled depression since we were teenagers and will probably spend the rest of our lives on medication.

My shrink didn’t mince words. He couldn’t speak to whether my child was developing depression, not without meeting her face-to-face. It could easily be a normal part of puberty, he said, but her chances of escaping the teen years unscathed are slim, given her parents’ history. Leafing through my file, he reminded me that I’d told him once that my own depression began when I wasn’t much older than she is now.

I read between the lines: It’s probably less a matter of if than a matter of when.

My troubled teens

I remember the summer I turned 12. It was the summer I thought I would die.

Our house was situated on a narrow strip of land between a set of railroad tracks and a river, my bedroom at the rear, closest to the tracks. On hot summer nights that year, no matter the hour, the rumble of the train would wake me from my sleep. I’d long since given up sleeping in my bed, opting for the living room couch, which was closer to the front of the house and therefore farther from the train tracks. As the house shook, I’d throw off the blanket, slip my feet into a pair of flip-flops and run out the front door, stopping only when I’d reached the riverbank, the farthest I could go and stay dry. This, I somehow convinced myself, was the only way to stay safe if the train were to derail, rolling down the bank and through my back yard, rolling into my bedroom.

My family laughed at me a lot that summer. They laughed me back into my bed by fall, when the lack of sleep caught up with me and pure exhaustion lulled me to sleep.

[Report: More than half of mentally ill U.S. adults get no treatment]

The train fears ebbed, but they were replaced by others as adolescence took hold. At 13, I spent days in complete silence, refusing to engage with friends, teachers or my family. By 14, I was throwing up regularly, fighting the image in the mirror with a vicious binge-and-purge cycle. At 15, faced with an option to graduate two years early from high school (I’d skipped the second grade, then taken advanced courses throughout high school), anxiety took over. Despite my desperation to escape my small town and even smaller high school, I balked and opted to stay home another year.

It wasn’t until age 17 — five whole years after a summer of running from the trains — that I finally got a name for the monsters doing battle in my head. I’d been frog-marched into the college campus psychiatrist’s office by a high school friend who had watched me spiral downward and who knew I was spending my nights in my dorm bathroom, a finger stuck down my throat.

The dual diagnoses: major depression and bulimia. One could cause the other, but the doctor couldn’t say which. When I returned home from college for Christmas break, I had a bottle of Prozac clutched in my fist.

By that time, I’d met the man I would later marry. He was managing depression, too. Today, we manage together. At times we’ve taken the same medications, grabbing from each other’s prescription bottles when our own supply was running low.

We know each other’s triggers.

By the time we’d been married for three years, we knew that we wanted to have a child, a little person who we hoped would be the best bits of both of us. She is. She has his dry wit and my steadfast belief in what is right. She has my blue eyes and his sense of direction.

What we didn’t think about was the worst of us and what that might create if we came together to produce a child.

Were we selfish?

Were we just young and stupid? Or were we selfish, throwing caution to the wind and sentencing our child to a lifetime battling a misery we ourselves wish we could escape?

Depression isn’t a death sentence. It’s not spinal muscular atrophy, the No. 1 genetic cause of death in infants, a disease that sneaks up on parents who don’t realize they are silent carriers of a condition that will claim their babies. It’s not cystic fibrosis, a condition passed down by, again, silent carriers, to children whose life expectancy is about 37 years.

It’s a disease we manage, a disease that — with medication — lets me get up every morning and work every day. It’s a disease I wouldn’t wish on my worst enemy.

But it’s the inheritance I fear I’ve handed down to the person I love most.

Read more:

Loneliness grows from individual ache to public health hazard

Harvard researchers discovered the one thing everyone needs for happier, healthier lives

Scientists open the ‘black box’ of schizophrenia with dramatic genetic discovery

It’s not just sadness. Happiness can break your heart, too.