Just out of the mouth of Art Harris live on Nancy Grace. He states he spoke with Misty's Grandmother in Tennessee who raised her during those early primary school years told him that, "Misty had a hard time in school, hard time doing homework, that she would cry and ask for help, the Grandmother had a hard time helping her and that Misty did have "learning disabilities". Finally confirmation from a family member, the one raising her, more likely the school began discovering these disabilities through testing.
Sadly, it was way too obvious something was going on. I'm even believing Misty borders "mildly mentally retarded". She needs a mental comp done, which could explin how she's not able to express herself correctly and what could be throwing LE off. Making them think it's inconcsistencies, but that's what you have with the learning disabled.