butterflypirate, except for the walking/talking development (my DD1 walked at 9 months... talked at 2.3 years). Those symptoms are a lot like my DD1. She has high functioning autism, and with that severe sensory integration disorder. There have been suggestions of ADHD and ODD, but we are focusing on the autism and sensory issues, and you know what? The others tend to not be as bad now.

We have been doing over a year of OT, some speech pathology and a bit of psychological behavioural work and she's a different child. We haven't had a meltdown in ages. I can not encourage hard enough the need for early intervention and getting them into a good OT as soon as you can.