Mentally ill people shouldn't have kids.
I am mentally ill myself. I have depression, CPTSD, and OCD. If your disorder heavily affects your emotional regulation and relationships, it's selfish of you to bring a child into this world while being aware of how your illness affects you and the people around you. Of course, this doesn't apply to individuals who don't tend to act out during an episode and are actively in therapy considering having a child or if you developed a mental disorder after having a child. But if you know that you have the tendency to lash out at people, avoid people, throw tantrums, and rely emotionally on somebody a lot, you should reconsider if being a parent is something you're ready for.
I've heard so many stories of parents with untreated disorders abuse their kids, I'm saying this in the nicest way possible, but why would you put anyone through that? I'm not saying mentally ill individuals are unlovable and don't deserve a family, but please, make sure you are stable and are actively treating your mental illness before you consider having a child. It's another story if you are mentally ill and you aren't aware, but the signs are often there too. But as I mentioned before, if you have a history of angry outbursts, splitting, and heavy emotional dependency, it's gonna affect your child in a bad way.