I Lived With My Stepson's Mom and Am a Better Person For It

We're happy to present this article by Ariel Rivera from one of our favorite sites, Yahoo! Parenting.

I was even more terrified to meet you than I was to meet the 2-year-old son that you and my then-boyfriend Dave had conceived while you were dating. Dave was nervous about us meeting too, so he suggested that I wait inside a coffee shop while he picked up Ethan by himself, but I told him that was crazy. If I was going to meet Ethan, I wanted to meet you, too.

Your name was Sarah and you were beautiful and taller than me. There was a fierceness behind your eyes that was intimidating, but I now recognize it as motherhood. Ethan was gorgeous and chubby in that way toddlers are when all of their joints present themselves as dimples. I was 26, lived in downtown New York, had little responsibility, traveled a ton, and had nothing to anchor me.

Per the agreement, Dave spent every other weekend with Ethan. After I met you, we took Ethan to the beach and I fell in love with your son. We ran into the ocean and we shrieked and jumped through waves. I told him the name for airplane banners and he ate mussels for the first time.

At that point, I was already living with Dave because like Billy Crystal's character says in When Harry Met Sally, "When you know you want to spend the rest of your life with someone, you want the rest of your life to start as soon as possible." That won't gross you out because you told my husband to marry me, before we even began thinking about it.

Over the next three years, Dave and I drove from New York City to Baltimore to see Ethan, but eventually we began crashing at your place on Friday nights so you could see your boyfriend and friends and inevitably, the three of us would stay up late talking and laughing over wine. I was Dave's loyal girlfriend, but I felt a female kinship with you. I want you to know that I've never patted myself on the back for making those trips because although I didn't yet understand what it meant, I knew you were the one doing motherhood.

After Dave and I married in 2012, we all lived together for two months — you, Ethan, Dave, and my seven-month pregnant belly — when you moved to New York so our kids could grow up together. When Dave drove me nuts, you took a walk with me around the neighborhood and understood my frustration like no one else could. People thought we were crazy, but your presence confirmed that the impossible had become possible.

I love it when people ask about our relationship. I will them to ask me how it all works so I can say that we do it for the sake of the child we love. And they ask — at Ethan's magic show performance, during first grade drop-off. We both know that my husband is oil and you are water — or as you describe your relationship, you were "brother and sister in another life" — and I am the emulsifying agent.

Sometimes we run out of clean pants for Ethan or forget to give him his lunchbox. But he also gets a brilliantly artistic mom who makes handmade Halloween costumes and schools him on '90s music, a science-obsessed dad who builds Lego sets and cooks pizza, and a stepmom who tracked down every playground with a water feature during the first summer he moved to Brooklyn. The adults get to share childcare costs and enjoy flexible social lives. And because of you, our sons are growing up together. And a personal plus: I got to see what a great father my husband was before we had a baby together.

The challenges are fewer. Once you make a commitment to being a blended family you are bound together, like it or not. None of us feel that we have permanent roots yet, but I think we all silently fear that someone will move away. For Ethan's sake, I've never acted like there was a difference between stepmothers and mothers. But for me, there is a very fine line between being a mother figure and a mother, and I've made choices that I wasn't always confident making. But you've referred to me as Ethan's third parent for years — I'm included on emails to his teacher and I'm an "emergency contact" on his medical forms.

But I am Ethan's stepmother. You are his mother. You carried him for nine months and slept next to him every night. You two have your own language. He is, ultimately, yours. I am comfort when you are not there, but similar to how I can still conjure the distinct childhood scent of my own mom. You are actually always there.

The difference became clearer when I birthed my own baby on New Year's Eve 2013 and I was congratulated on becoming a mother. I fell in love with my son so immediately and desperately that I could have burst into flames. I've never, for a minute, thought of your son as a "practice kid," but being Ethan's stepmother has absolutely made me a better mother.

Fairy tales aren't written about young women who fall in love with men who already have children with their ex-girlfriend, but if I am lucky enough to live to age 100, I'm glad I got to raise a child with both of you, only a quarter of the way in. It is possible to live the life you didn't imagine and live it well.

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