My nephew is 6, and he used tippy-toe all the time. SIL didnt do anything about it when it started because she was told it wouldnt affect anything. Recently she has had to spend heaps at podiatrists & doctors because it damages the tendons in the back of the heel, and doesnt allow it to grow properly. Now he has to have special inserts in his shoes and he has this "wedge" to stand on when he cleans his teeth, coz thats the only time he stands still for 5 mins, it makes him stand with his feet angled upwards.