Where a child appears to need extra support due to a learning difficulty or disability, the maintained school or local authority must usually decide whether the child has ALN.
Os yw'n ymddangos bod angen cymorth ychwanegol ar blentyn oherwydd anhawster dysgu neu anabledd, rhaid i'r ysgol a gynhelir neu'r awdurdod lleol fel arfer benderfynu a oes gan y plentyn ADY.