It is possible that the main title of the report Marfan Syndrome is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.
As Jenny points out, being able to lisp the alphabet song at age two has little to do with 'knowing' the alphabet. And, yes, most children learn the letters by sight and sound in kindergarten, although most are capable of learning this information sooner if diligently taught by parents or others.
Comprehension also should increase â by 3 years of age, a child should begin to understand what it means to put it on the table or put it under the bed.. Your child also should begin to identify colors and comprehend descriptive concepts (big versus little, for example).