I don't want to further derail this thread, but one thing I'd like to say is that, AFAIK, TM was investigated and cleared. I don't have a link, but I'm pretty sure that his time logs were checked to verify his absence from West Memphis at the time. The only reason, IMO, he could remain a suspect is if the TOD could be definitively established as being after 6 am on May 6th, which is when he returned to West Memphis, IIRC.
IMO, JMB was likewise investigated and cleared (although I know others disagree). IIRC, the "natural" fathers of SB and CB were likewise cleared of the crime. The only male parental figure who was not investigated and cleared was TH. When this fact is considered in conjunction with other physical evidence that has been revealed since the crimes (bite mark, mtDNA), IMO clearing TH should be the focus of any investigation and/or discussion. Although I'm open to new information about others, IMO clearing TH should take precedence. I'd love for someone to provide proof (from someone other than TH) of his whereabouts at certain critical times on May 5th and 6th. I cannot, and that's why he remains at the top of my suspect list.
As to the mothers, although I'm not naive enough to believe, as they did in Fall River, Massachusetts, that a woman is incapable of such a crime, historically, women don't usually murder by using strength, which is how these murders occurred. Maybe that's why the mothers were never investigated. JMO