Sometimes expecting mothers try to be nice to others, and make an effort to be an overall good person. I understand both of those things are difficult for you, but you should try that.
I am not sure why Dammitt was banned, but as far as I can tell, the other two accounts have not caused any major problems or trouble in the ~6 months since Dammitt was banned. Assuming whatever Dammitt did to get banned was not especially disruptive, I would suggest moving on.
Why have rules at all if the forum is not going to enforce them?
Still, I think what QS said is logically right, they have not done anything harmful rather and moving on is the most humanitarian move.