If there is a risk of imminent harm to your daughter, you do have the right to withhold parenting time. However, I would urge you to get an order from the court before you let too much time elapse. The quickest way to get that order would be to hire an attorney and have the attorney file an ex parte motion for extended parenting time. That should give you the time you need to figure out why the other children were removed from your ex's home.
As for getting a copy of the CPS report regarding the removal of the children, you are only entitled to CPS information regarding your child. So unfortunately, you probably won't be able to get anything there. But if you know which police agency came to the house, you may be able to file a Freedom of Information Act request for the police report and see if that sheds some light on the situation for you.
What happens might depend on whether this was the first involvement of CPS, or whether they have had contact with her in the past regarding abuse or neglect. Generally speaking, when children are removed from a home and made wards of the court, they can be placed in foster homes or be placed with a relative. The ultimate goal is to reunite a family. Do you have a custody order for your daughter, and the mother have only parenting time every other weekend? If that is the case, you could withhold parenting time if you believe your daughter is in imminent danger. I would contact CPS and let them know that you have your daughter. If you don't have a custody order, but she has a custody order for your daughter, CPS may advise you to withhold parenting time. If it was me, I would go back to the court to request an order for the relief you are requesting...no parenting time, or restricted/supervised parenting time, pending CPS investigation, if one is being conducted.
As Mr. Stephan stated, unless your daughter is subject to the action taken by CPS, you would not be entitled to a copy of the CPS investigation and findings.
Neil M. Colman
Mr. Colman is licensed to practice law in Michigan. The response herein is not legal advice and does not create an attorney/client relationship. The response is in the form of legal education and is intended to provide general information about the matter within the question. Oftentimes the question does not include significant and important facts and timelines that, if known, could significantly change the reply and make it unsuitable. Mr. Colman strongly advises the questioner to confer with an attorney in your state in order to ensure proper advice is received.