The obvious answer is to talk to them. Hopefully they give you a cell phone and then you can just text them when there is an issue.
Also, you and your wife can meet the child and work with the parents so you can form a bond/trust so he will be more likely to listen to you. At least you can learn his name.
Also, you and your wife can meet the child and work with the parents so you can form a bond/trust so he will be more likely to listen to you. At least you can learn his name.