If I understand you correctly, her probationa ended and you dont have to copy the bosses but you did and she asked you not to do that again.
If there is no requirement to copy the bosses on a demand to her to catch up on her work, then don't but include a phrase that within a certain amount of time, if she does not address your concern that you will contact that bosses.
Finally, tell her that none of this would e a concern at all for anyone if she would just buckle down and do her job.