The following information may help to address your question:
Toe walking is not typically an early sign of CMT1A, rather more often it is a "slap foot gait" due to weakness in the lower legs (foot drop). Clumbsiness or frequent tripping are other early signs. As CMT1A progresses a person may develop tight heel cords. Children with tight heel cords often walk on their toes, however toe walking is a common habit among unaffected children as well.