Sounds like a weird combo of fetal alcohol spectrum disorder, reactive attachment disorder, autism and maybe other unknowns. I would get her on husband's insurance and take her to both a neuropsychologist AND a pediatric neurologist for a total workup, physical and otherwise. I wish I had done this.
Do you have any children younger than her? How does she treat animals?
My heart goes out to you. This obviously happened a lot during pregnancy and from lack of attention from her primary caregiver. This used to be called failure to thrive. Now it is called reactive attachment disorder.
Alcohol is poisen to a developing fetus, but you can help her to reach her potential! I am sure you will.
Prayers for all of you. Hoping for a better future for this child. I am sure that your care and kindness will make a big difference.