It's sad that I stumbled across this thread after it died out. I am actually one of the grandchildren of Marilyn and Ernie. I have not had contact with the Pratt side of my family in 30+ years. I read through the theories and speculations that have been said. I will sum up the story I have heard from my mother on this subject which has left me with nothing but questions for at least 20 years. I was told that Marilyn had disappeared after a supposed meeting with Ernie. I have heard that there was a long standing abusive situation stemming from Ernie and his alcoholism and anger. My biological father had told my mother that he remembers seeing what Ernie had done to his mother when he was drunk. Details were never fully expressed, but it was a volitile situation. I cannot recall if it was Lance or Marvin that had the concern of Ernie burying Marilyn in the basement. It was a dirt basement that Ernie decided to have cemented in after the disappearance. I am unsure if the police ever followed up. From what I recall of the story as well, her car was found a day or two after her disappearance. I was informed Ernie slept on the couch after the disappearance. There was speculation that Ernie had accidentally killed Marilyn in the bedroom and that is why he quit sleeping in there. There has been so many things I have read online, to hearing from my mother from stories she heard from her ex family-in-law. I was informed too that Ernie went cold if Marilyn was mentioned. My mother told me that he made her feel uneasy and uncomfortable but she could never explain the feeling or reason until a later incident in her life. (one of her bingo hall customers was Robert Lee Yates).