“Is that your son?” the man suddenly asked, without any preamble, and with an aggressive edge to his tone.

I was sitting in the dining area of a local Whole Foods after finishing the weekly shopping with my 3-year-old son, Zephyr. We were both eating and laughing about something silly, simply enjoying a Saturday morning together.

The unexpected question was from a 30-something African American man who had been giving me odd, furtive glances since we sat down. I figured that he thought he recognized me and was trying to jog his memory. I was certain we hadn’t met, so I was bracing myself for one of those semi-awkward, “No, sorry, I’m not who you think I am” conversations.

“Yes, this is my son,” I answered, a little warily.

“Hmph,” he snorted. “I didn’t think so.”

Now my defenses were fully up. “Why not?” I shot back.

He scrunched up his face, like he had just taken a bite of something distasteful. “There’s just something off about you two,” he said.

Frankly, I wanted to knock him senseless, but I restrained myself. Who says that to a complete stranger? How could he not see — for any number of reasons — that Zephyr and I were related? In my mind, there was only one reason why he would draw that conclusion.

“Is it because we don’t have the same skin color?” I challenged.

You see, I’m white and my Ghanaian wife is black, so our mixed-race son is golden brown.

Now he was on the defensive. “Why would you say that?”

“Because he has been calling me ‘Poppa’ since we arrived, he looks like me, we’re clearly very close and I’m obviously his caregiver,” I replied. “There’s nothing else.”

He huffed and he puffed, but I knew my verbal punch had landed. I left with Zephyr a moment later, unwilling to spend time around such negativity. It wasn’t until I was sitting in the car that I realized how upset I was. I was angry this stranger would question my paternity of my son, because he couldn’t see past his own biases and stereotypical visions of a family. I was heartsick he couldn’t see the love and connection between Zephyr and me. And I was outraged that anyone would think they had a right to confront a parent in such a way.

Unfortunately, my experience is in no way unique. As I began telling this story to other parents I know with interracial children, I kept hearing variations on it over and over again. It seems complete strangers have no problem making prejudicial assumptions about families who don’t have uniform skin color — and then confronting the parents about it in a way that is deeply hurtful. Some tales were far more disturbing than mine.

My Salvadoran friend, Javier, is married to a white woman, Ashby. They have a sweet, round-cheeked and light-skinned daughter, Nina. When she was about 6 months old, Javier was taking her home alone after dinner with friends. It was late, so Nina was tired and crying. He was at his wits’ end as he tried to soothe her and strap her into her car seat.

As he was doing so, a woman in an apartment overlooking the street opened her window to ask what was happening. He replied that he was simply trying to get his cranky baby into his car and figured that was the end of it. It wasn’t. A few minutes later, as he was still trying to calm Nina down, a police car pulled up. The officer got out and began quizzing Javier. What was he doing? Was this his daughter? What was his address?

Javier replied that Nina was his daughter and he just wanted to get home. Why was he being treated like a criminal? The officer said someone called in a suspected kidnapping.

Other stories are less confrontational, but no less painful for the parents. My Ghanaian sister-in-law, Yom, has two mixed-race children with her white husband, Jared. The first time she took her daughter, Penelope, to the playground someone asked if she was her daughter’s nanny. It still happens about twice a month and the question comes from both fellow parents and nannies.

Another mother I know, Ana Maria, an Ecuadoran, is married to David, a white guy with a touch of Puerto Rican. When she began taking their interracial son, Luca, to the library, other mothers and nannies assumed she was a nanny. One nanny even asked her how much she got paid an hour. At first Ana Maria patiently corrected them, but she grew frustrated and offended as time went on, as the same people kept making the same incorrect assumption. She began to dress up — goodbye yoga pants, hello pearls — before going out with her son in an unconscious effort to set herself apart from the nannies. Once she realized what she was doing, she was shocked and stopped doing it, but it made her realize how much she was hurt by people’s assumption that she couldn’t possibly be the mother to her own son.

It’s depressing to hear mixed-race families are still subject to such shortsightedness and bigotry. Though such families are becoming more common — a 2015 Pew Research study found that multiracial babies accounted for 10 percent of births in the United States in 2013, up from 1 percent in 1970 — this reality still has not sunken in to some segments of society.

This lack of enlightenment seems to give nosy strangers — who lack decorum, delicacy and decency — the perceived right to question other peoples’ choices, or to make assumptions that are deeply upsetting to the parents.

Let me be crystal clear: It does not.

I feel like I’m speaking to kindergartners, but here are some tips for anyone thinking of questioning someone else’s family arrangement: Mind your own business. If you don’t have anything nice to say, don’t say it. Apologize if you hurt somebody.

And if you’re one of the parents of an interracial child who is questioned about your position in your child’s life, do what I plan on doing if it happens to me again: Start a rational conversation. You just might change someone’s mind about the endless possibilities of the modern family.

Martell is the author of several books, including his most recent: Freak Show Without a Tent: Swimming With Piranhas, Getting Stoned in Fiji and Other Family Vacations. He tweets @nevinmartell.

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