Are there symptoms that predict a reading disorder in children?

Reading disorders: There are none that are very reliable, but some that are suggestive are: making letter or number reversals when writing (this can be normal if only temporary, but if persistent and frequent, it's a problem); severe inattention when being taught on a blackboard; unusual frustation with school experience; school avoidance behaviors.

Yes, beginning with: family history of Specific Language Impairment &/or Dyslexia. Early Expressive Developmental Language Disorder with or without Receptive DLD increases risk even if language "catches up" by 4. Persistent Expressive DLD past 4, diagnosed as SLI, carries a 40-75% risk of Dyslexia. Deficits in sound-symbol association, like P-puh, in pre-school & in phonological awareness in KG are highly predictive.