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Thanks for bringing your question to JustAnswer.
I think that you are right to be concerned. The best indicator of future behavior is past behavior (unless the person commits to, and completes, therapy for the issue.) You have already noted a non-maternal attitude toward your daughter. It would be wisest to wait to have a child until you know she has worked on the issues from her childhood, and it's reflected in her improved treatment of your child. It's possible that her insensitivity to your child would increase if the two of you had a child together at this point, because someone with this much insensitivity would likely play favorites, which wouldn't be good for your daughter.
While it isn't your partner's fault that she didn't have good role models for parenting, it doesn't seem wise to bring another child into the picture until she has worked on her insecurities and lack of attachment to your child.