Honestly after reading about Kuvira's backstory and reading some analyses on her character, I would be totally fine if Kuvira has a story where she hunts down and kills her birth parents. She was obviously an unwanted child born to two non-bending parents and to top it off she was very hard to control and could escape punishment due to her being stronger than her parents. Kids aren't as oblivious as we like to think they are and her acting out was her wanting to be acknowledged by her parents the way she always wanted. In a fit of rage when she nearly killed her mother in an earthbending outburst, her parents totally washed their hands of her unceremoniously dumping her off with Suyin with no warning and never reconnecting with her at any point in her life. Like damn, it's honestly a miracle she didn't end up as insane as Azula.