Reflecting upon this some more, it is Elise’s professional responsibility to resolve this and clear the air to enable an effective working environment.
So far she hasn’t taken any action. Now, it’s only a few days after her start date. Perhaps she needs the weekend to reflect on it.
She must be aware that the situation is a major issue for team dynamics and trust. It is her responsibility to talk to you, apologise for the past, explore how you can have a healthy working relationship, and take action to make it work. This is a reasonable expectation of a professional person.
If I were team leader and aware of the situation, this is the approach I would take.
It is not within employers remit to judge people for their personal life and distant past,
It is within employers remit to judge their work behaviour now.
I would give her a few more days grace to resolve the situation independently without prompting.
Then if nothing happens, I would arrange a one to one with her and express my concern about her CURRENT behaviour. I would put the onus on her to make a plan to resolve this to enable her to continue her role effectively. If she did not respond positively I would record this formally as a performance issue. I would make reference to relevant policies and her contract, which hopefully contain clauses about expectations for working with others.