A Waupun man accused of sexually assaulting a three year old boy has pleaded not guilty to charges against him. 26 year old Robert Moungey entered the plea at an arraignment hearing Wednesday in Dodge County Circuit Court. He’s charged with first degree sexual assault of a child. Police learned of the alleged abuse from Moungey’s wife, 25 year old Cassandra Scheuers. Scheuers is also accused of sexually assaulting the three year old and is charged with first degree sexual assault of a child. A scheduling conference for Moungey has been set for August 20th.