Bright child can't retain letter names?

I also think we may be dealing with attachment issues and/or control issues here. But then again, I am fairly sure there was prenatal exposure that could be having an effect. She still has a lot of fears and anxiety, so maybe she just can't devote the energy yet to all the developmental tasks. For now I am continuing to work with her. She does seem proud when she can name a letter. The only letters she can easily recognize are the ones in her name. Other than that, she gets B right 50% of the time, and we have been working on D and E (one at a time) for weeks now. Only rarely can she identify them more than 5 seconds past when we worked on them. I knew a child with what I thought dyspraxia (according to his mom). He could not speak at all. Maybe I am mixing up the name. I assume his case was pretty severe. Anyway, a neurological evaluation may be a good idea down the line, to try to determine what damage was done by exposure to Meth both before and after birth. Thanks for all the input!