Please tell me the symptoms of mental retardation in a toddler?

Delayed development: Sitting up, crawling, walking and speaking words all delayed significantly, bearing in mind that there arae wide differences in normal toddlers.

Definitions: Generally, global developmental delay is the term used at that age. If testing shows a toddler's overall functioning to be < 50% of what it should be for his age, he is at risk for intellectual disability ( formerly mental retardation) when tested at age 6. Another clue is lack of significant progress over time, despite having early intervention services to increase his rate of development.