Legal Question in Family Law in Missouri

Re: I believe that my wife is committing adultery

No, generally speaking the court may only consider marital misconduct such as adultery in dividing the marital assets and in considering the issue of maintenance. It is not relevant to the question of child custody unless the spouse has taken some action that is, or threatens to be, harmful to the children. There are many ways to offer evidence of marital misconduct. Phone records, credit card records, private investigator's photo's or video's, computer records, and the testimony of witnesses are just a few examples. If you have not already hired an attorney, I would strongly suggest that you do so promptly and follow the advice of your attorney. Good luck.