I suspect autism
Two paths to understand diagnosis, depending on where you are.
Beginner level — first steps

The Map to an Autism Diagnosis
A practical guide for those just starting out: understand how an autism diagnosis is built and what the first steps are.
Ideal for parents and caregivers with early questions.
Intermediate / advanced level

The Autism Bible
How a pediatric neurologist builds diagnostic reasoning step by step, with depth for those who want to go further.
For families who want to deepen their understanding and for health and education professionals.