Of course if you suspect or witness child abuse occuring contact 911 immediately and report the incident to a local Michigan Sheriff's Deputy. 

A complaint of child abuse and or neglect can be made by any person, including a child, who has reason to suspect child abuse or neglect. The complaint may be reported to the Department of Human Services or any Deputy or Police Office in the state of Michigan.

Contact the CPS Emergency Contact Numbers in your county to make a report of suspected child abuse and or neglect.