My first girlfriend is now a part of my family. It’s going to send women running.

Care and Feeding is Slate’s parenting advice column. Have a question for Care and Feeding? Submit it here.

Dear Care and Feeding,

“Tara” was my first girlfriend from eighth grade until we graduated. Her home life was really, really horrible.

So she ended up moving in full-time with my family when we were 15. I had already fallen out of love with her, but felt guilty, so we went through the motions until graduation. I went to college; Tara stayed living at home.

Long story short: My parents officially adopted Tara while I was in college, with my blessings. She was already calling them mom and dad, and my parents always wanted another kid. Tara and I messed around but never had sex. I consider her like a cousin at this point and would call her my foster sister when asked about my family. My dilemma is that I am ready for a long-term relationship, and I don’t want to lie, but telling someone my first girlfriend was my adoptive sister, who still lives with our parents, isn’t the best icebreaker.

I also had bad experiences of falling for girls who seemed cool with me being friends with my exes (I never really had a bad breakup), and it turned into a big deal. I’d be in a month-long relationship where I would accept going out for drinks with old friends, my ex would be there, and then I’d get grilled when I got home. So, what do I do about the Tara situation here?

—Ready to Settle Down

Dear Ready to Settle Down,

Things become weird when you make it weird. Families are formed in all kinds of ways, and maybe this is because I’m 40, but I wouldn’t be weirded out if I were dating someone in this situation. I would, however, feel strange if the information wasn’t disclosed. Going about it that way would make it feel like some kind of dirty secret when it doesn’t have to be at all.

When you start dating and getting serious with someone again, be honest about who Tara was to you and who she is to you now. Be open and don’t keep any secrets or tell any half-truths. The truth will pop up later, which is what makes for arguments.

Also, keep in mind that you’re both adults now. Being friends with adult exes and teen exes is a bit different in most situations. But especially in this one. Anyone you are dating now shouldn’t see your relationship with Tara and you being around her in the same way they would see you going out for drinks with a recent ex.

The key here will be ensuring that your future girlfriend feels secure in her relationship with you. Some of this will, of course, involve her being a good match and not having unrelated insecurities that sneak in. But build a relationship with her that is based on that honesty and openness, and when she feels safe in her connection with you, it’s less likely she’ll be upset just at the thought of you being around someone you really only see in a familial way.

—Arionne

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