You haven't really provided enough detail for any reliable answer to be given IMO. Also, this isn't a family law issue. For what it's worth (if you're actually serious), it's difficult to say whether it'll be investigated. That would come down to whether you were able to identify the person, and whether the police find the story credible enough to take further. If it's an anonymous tip, I'm guessing you would have needed to provide enough evidence of the crime for the police to pursue without the need to contact you for more information/witness statement. If they don't feel the information you've provided is sufficient to prosecute, it'll likely go into the 'unsolved mysteries' file.
If you genuinely think you've made a mistake, you should probably say so. A genuine misinterpretation isn't a crime, and I very much doubt the police would pursue anything against you.