“I’m a 30-year-old man with a 6-year-old daughter.

We aren’t biologically related. I was close friends with her mother since childhood, but we were never romantic. She had her daughter with her husband, but when the baby was still a newborn, both parents passed away in an accident. After that, I felt responsible and adopted the baby.

A few weeks ago, at a family dinner, my new sister-in-law saw an old photo of me with a friend and asked who she was. I told her that she was my daughter’s mom. The next day, without telling me, my sister-in-law did a DNA test on my daughter and showed me the results. She didn’t know my daughter was adopted, and she assumed I was her biological father.

For context, my family knows my daughter isn’t biologically mine, and even my daughter knows she’s adopted. I never hid this from her. Most people just assume I’m her biological dad, but I don’t usually correct them.

When my sister-in-law showed me the DNA test, she accused me of ‘raising a dead woman’s affair baby.’ She said this in front of my daughter and family. I just stared at her and then started laughing.

I told her I knew my daughter wasn’t biologically mine because I adopted her. My sister-in-law got angry and left. Now, my brother is upset, saying I embarrassed her. But I think she embarrassed herself by testing a child that isn’t hers and then showing the results.

My brother thinks she was just trying to help, but I think she crossed a big line.