CPS is enforcing the law. According to Maryland law children under 8 require supervision. The supervisor must be at least 13.
Don't blame CPS for doing their job and enforcing the law.
CPS has carte blanche to enforce whatever subjective standards they wish, whenever they wish.
A very good friend of mine who happens to be a paramedic says he routinely gets calls from a particular school/CPS case worker for minor behavioral issues (e.g., temper tantrums, minor disruptive behavior). Because CPS calls the ambulance, he is required to visit the school and take the child to the hospital (of course, one affiliated with CPS) for psychiatric evaluation. This happens, of course, without the parents' knowledge. It works for everyone- takes the kids of the school's hands, justifies the CPS case worker/hospital and paramedic's salaries. He hates it, understands the economic waste and self-serving nature of it all, but is obligated to do it. He says the kids always have a great time riding in the ambulance, so that's something I guess.