Yes, it can be addressed without involving the police. Just don't call them.
If you do call the police, your son could be charged with a domestic battery. The police would treat him as a juvenile. They could deal with on their own with a station adjustment or they could refer the matter to the court. From there, there are too many possibilities to answer adequately online. You need to speak to an experienced criminal defense attorney in person.
If you involve the police, your next step will be looking for an attorney to represent your son. If she is afraid of his actions in the future, she can seek an order of protection.
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Whether it can be addressed without police involvement depends entirely on whether or not someone calls the police. If your daughter, or son-in-law, want him arretsed, there's a good chance the police will arrest him and refer the case to the state's attorney for consideration of a Petition for Adjudication of Wardship (the juvenile equivalent of criminal charges). If this occurs, you will also be named a Respondnet in the Petition, meaning you'll have to appear in court with your son.