From "Star Trek: The Next Generation: Redemption II (#5.1)"
[Picard has asked Sela about her mother, Tasha Yar
One night, when I was four years old, she came to me. She bundled me up and she told me to stay quiet as we left the compound. I realized she was taking me away, she was taking me away from my home, my father... So I cried out. My father offered her life, he gave her a home, he gave her a child - and how did she repay him? By betrayal. They executed her!
[she turns away and looks out the window for a moment, then turns back
Everything in me that was Human died that day with my mother. All that's left now is Romulan. Never doubt that.