My daughter, dysphasia, do not understand what it is told, she 4½ years. She has enough strength to let go of our hand and go like a bullet. So be it a mountain or any place or there is danger, we take the backpack. It is true that the position of the strap at the top of the bag tends to unbalance the child and would have perhaps been better in the center of the bag. But, it is better to fall on the buttocks that this run over by a car. I always hold her hand, to teach him, but I put the strap around my wrist loose and if it is blocked. Given the number of times it has shot to go, this bag remains pretty solid overall.