Training and Educational Pathways for Clinicians (Post-graduation) for the Assessment and Diagnosis of Autism Spectrum Disorders: A Scoping Review.

Curran et al. (2025) watched one pair of identical twins who later got a Rett syndrome (RTT) diagnosis. They tracked every tiny movement and sound from birth until age two.

The team filmed the girls each week. They scored when the babies lifted their heads, reached for toys, cooed, or made eye contact. Parents kept daily logs too.

Both girls showed small but clear delays before six months. They lifted their heads less often and made fewer babbles than typical babies.

At nine months the gaps widened. Hand-use looked shaky and eye contact dropped. These signs showed up months before the classic RTT regression hit.

Stewart et al. (2018) found that older kids with RTT walk poorly when their feet press the ground unevenly. Christine’s work says the motor story starts in infancy, not after regression.

Osório et al. (2025) saw that autistic toddlers walk with wobbly, uneven steps. Both studies prove you can spot atypical motor control before age two, just in different disorders.

Barton et al. (2019) created a five-item checklist that flags autism in under-threes. Together with Christine’s case, the message is clear: watch early movement and communication no matter which developmental disability you suspect.

If you assess babies at risk for RTT, autism, or any developmental delay, add a quick motor-communication checklist to your routine. Look for shaky head control, limited babble, and uneven hand use before six months. Catch the signs early and you can start therapy months sooner, possibly softening later skill loss.