My mom never stopped smiling when things were hard. I learned it's a leadership superpower.

• Growing up, my mom was always smiling.
• She was always looking at life with the glass is half-full mentality.
• As a lawyer, I now see the power of a big smile.

My mom's positivity is pervasive. When I was a teenager, my parents took my sister and me on a backpacking canoe trip in the Adirondacks. It wasn't the sort of thing we did often, and our heavy canoe was difficult to carry through the necessary portages. On one particularly steep, weed-riddled stretch, Mom struggled with Dad to get the canoe over the hill. Every time they set it down for a break, she'd shake her head, smile, laugh a little, then continue onward until the canoe was back in the water.

That's how I meet challenges today, but growing up, I didn't always appreciate Mom's glass-is-always-half-full attitude. I wanted to be a successful leader, and to be a leader, especially as a woman, I knew I needed to be taken seriously.

Though I didn't put much stock in smiling or laughing, Mom passed those traits on to me without my intention.

When I smiled too much, I worried my other skills would be overlooked

"Good at smiling" isn't the sort of thing that goes on a résumé, and I long dismissed its value, even as I smiled and laughed through college, then law school, and then climbed the ranks of a multinational corporate law firm.

The first time I recognized the power of a smile in a professional setting was my sophomore year in college, when a business professor said, "I really appreciate how you always come to class with a smile." At the time, happy wasn't a word I'd use to describe myself. But he was right. I smiled and laughed a lot.

Yet, more often than compliments, my tendency toward smiling caused others to overlook and even dismiss my other credentials.

When I was offered a position at a prestigious law firm, my then-boyfriend said, "Of course you got the job; you have an attractive smile." He said nothing about my other qualifications, like graduating magna cum laude from Georgetown University or being at the top of my class at Columbia Law School. No, it was just about the smile, and he was an echo of what I heard from the larger culture: Don't smile too much, or your other skills and talents will be overlooked.

I learned smiling was an undervalued leadership superpower

While practicing corporate law, staying calm amid high stakes and demanding deadlines was a crucial skill. But it wasn't until a senior partner told me my smile put him and clients at ease, that I recognized how my ability to stay calm stemmed from the way my mother modeled positivity by smiling in the face of challenge.

Whether I was presenting to the Department of Justice, managing a team of over 100 lawyers, or responding to an urgent client request, smiling enabled me to do the job more effectively.

It wasn't just how the positive energy calmed others, but perhaps more importantly, how it calmed me, too. Smiling enabled me to stay present and attentive during many frenzied moments at the office. Indeed, science supports this. A study found that smiling reduces the body's reaction to stress.

My mother's smile not only carried me through some of life's most difficult moments but enabled me to find success in a demanding, high-stakes career. From the vantage point of age, I now understand that an ability to smile and laugh often, when combined with hard work and intelligence, makes for a powerful leader.