Welcome to the group.

I also have a daughter with spastic diplegia, auditory processing and vision issues and ADHD.

She started on Adderall XR at age 5, while redoing kindergarten.

Every child is different, but for her, the results were outstanding.  It took maybe three months (including an upward dosage adjustment) for it to really be evident, but suddenly she understood and conversed more as her auditory processing got much better.  Behavioral problems in school vanished.  Her drawing and handwriting improved dramatically along with her focus.  It just seemed like it helped organize her brain.  

By the way, her neurologist predicted it would make her symptoms worse -- I was at the end of my rope and willing to try it anyway.  She has been on Adderall for 5 years now, and doing well.  Twice we briefly tried other ADHD meds, but neither worked as well in her case.

Good luck!