Yes, they are 4, children develop speech and the ability to say words around 9 months old, by 4 they should have developed over hundreds of vocabulary words and should be able to read sight words as well as form hand written letters, not well, but a foundational beginning should be there. By kindergarten they should be able to write sentences and learn grammar. By 4-5, they should also be able to do basic math, addition and subtraction.