I am white and my children are mixed race. I'll never comprehend the taunts they've had to endure.

• My children are biracial and products of a cross-cultural marriage.
• Strangers have asked before whether all my children are adopted because they don't look like me.

When I look at my five children, I see my mother's eyes, my brother's hair, and their father's dimples. I see features from my own face, but I don't notice the slight variation in skin color that distinguishes them most obviously from me. Their warm, tanned tone links them to their dad in a way they can never be connected to me.

My children are products of a biracial, cross-cultural marriage. Their father is a resettled Cambodian, and I'm a Jewish white American.

But if you ask them about their ethnicity, they're likely to respond with questions: "What do you want me to be? What do you think I am?"

Even when I press them to tell me why, they refuse to answer. Maybe it's because for them an explanation is long, unwieldy, and none of the asker's business.

That's always fascinated me. I consider their mixed heritage a point of pride. It makes them unique and gives them an opportunity to stand out in a crowd. Though they're now adults, my kids didn't want to stand out growing up. They'd much rather blend in and thus fit in.

Being the parent to multiracial children

The US Census Bureau said that the number of people who identify as multiracial has doubled in the past decade. In fact, "multiracial" is the fastest-growing category of Americans.

Because I'm a white mother of multiracial children, more people question my relationship to them than their dad's. When our kids go somewhere with him, it's rightly assumed that he's their biological father. It's not the same when I go out alone with them.

I remember shortly after giving birth being asked by a sales associate in the local pharmacy when we'd adopted the baby. I couldn't understand how she'd made that assumption. I thought he looked like me, so I sputtered: "He's mine. I just gave birth to him."

My daughter is adopted. Those who don't know that wonder why she doesn't look like the rest of the family. Yet all I see are similarities. In my favorite photo of us, our facial expressions match.

Cultural awareness has always been important to me, so when our kids were little, we immersed them in Cambodian culture. But my husband and I split up. After the divorce, the children had fewer Cambodian cultural experiences.

When it comes to my Jewish heritage, I don't have much to share. I grew up pretty secular, and my family practiced few religious traditions.

Recently, I found out that my children also heard racist remarks about being Asian. In response to an invitation to his birthday party in elementary school, a girl told my son, "I'm not coming because you eat dogs."

It took a long time for him to tell me this. He was concerned I'd be the one to feel hurt. That made me wonder how many other cruel comments they'd endured.

It breaks my heart, but I have no doubt there have been plenty of slights and slurs. Since I've never had to endure such taunts, I don't think I'll ever comprehend what that feels like.

In a world that categorizes people by how they look, I'll always stand apart from my kids. I don't think I'll ever fully understand how they see themselves and how they feel about who they are. Nor will I know their correct answer to the question "What are you?"