RedactedNarrative: A personal watercraft was pulling a water skier. The skier lost a ski and fell down. The observer (skier's sister) jumped off to assist her brother with the ski when the rope got tangled around the boy's wrist. The rope got sucked into the PWC motor and dragged the boy under the PWC. The Operator (boy's father) jumped in the water with a knife and pulled his son above water. The rope was cut off of the son's wrist which was very badly cut, but hand was still partially attached and he was transported by boat to shore for medical treatment. Life jackets were being worn by all. Alcohol was not a factor. There was no damage to the PWC.