They're concerned about the baby, believe it or not, because the baby was present.
You have rights and you need to know how to exercise them. First, never trust CPS. They're not your friend. CPS NY -- don't get me started. They're not usually that good and will do some really stupid things, in my experience. They will also try to take advance of you.
Okay thank you for that information. That's going to help you.
For example, if they claim something happened on 5/28 to your child but they don't interview you until 6/6, you should be telling these social workers that obviously no “imminent danger” exists or they would have acted on the report right away! If you don’t stand firm and point out their mistakes, they will walk all over you and violate their own laws in many different ways.
The CPS agents will want to talk to your children alone. Just say “NO”. Tell the agents that your child has the right to have an attorney present, and that if he/she insists on an interview then you and the attorney will be present and the interview will be recorded, preferably on videotape. Of course, if your child is attending a public school, you probably won’t get a chance to say “no”. What would happen is that the social worker would go to the school and, behind your back, get permission to talk with your children from the school employees. You can tell the school ahead of time (in writing) that you don’t permit such interviews, or anything other than basic education activities, however you cannot trust school employees to go by your wishes. It might help to ask your attorney to write a letter to the school forbidding interviews with CPS workers.
Also, your kids are very young, and it is understandable that they would want you to be present, so you can object to this because they will be frightened. You have the right to be there. Don't let CPS bully you, which they will. They want to know if the baby was present or if anyone of the other kids heard the fight.