I'm not going to reach out and warn an ex her kid (possibly mine) may have a genetic blood disorder
Why are you not going to tell her?
She is evil, she deserved it.
Sorry to hear about blood disorder, but you really should tell your ex about it. Your child shouldn't suffer because of the relationship you have with your ex.
I don't give a shit about my child. So what if I've done this.
That sounds angry, you should not take out your anger on the child. You should bring up the disorder because you need to protect them from potential harm.