What to do if i don't understand how one can have both autism/asperger's and adhd simultaneously?

Brain development: Dear shelly, this is a difficult question because asperger's, autism and adhd are still incompletely understood problems of the developing brain. Each child/person with any of these labels is unique with strengths and weaknesses. Often with these developmental diagnoses there are overlapping symptoms which doctors call co-morbidities, like many overlapping circles. Hope this helps.

Autistic Spectrum : Disorder & ADHD are neurodevelopmental disorders, each with its own set of criteria. When a person has one alteration in brain structure &/or function, her risk of having another is greater than that of the general population. 40-70% of people with ASD have ADHD; 35-65% have Intellectual Disability. If ASD & ID co-exist, the incidence of seizures goes up. They just pile on in a most unfair manner.