Dream of bike, space, mad

I dreamed about watching a father with his sons and each with their bike. The youngest boy was the one who went behind the others. Then, there was some kind of space that they needed to 'jump' over with their bikes. All the boys made it, except for the youngest who was doubting, he did not believe he could do it. As he made the jump, I knew he had not put enough effort and would not make it to the other side. The boy grapped the side of this space, hanging in order not to fall. His father did not move to help him, he just watched the boy and expected him to climb up and get on the ground. The little boy was crying, and surrendered and fell. While everybody, including myself, thought that it was not a long fall, and that he would just fall on the ground a little below, I realized that there was no ground below, and that he had fallen a long distance, killing himself for sure. When his father realized this, he went mad, I had a terrible time, realizing I had not done anything...