RedactedNarrative: Operator 1 was drifting and hit the gas to start moving then took hand off throttle to sit again.  Operator 2 of striking vessel believed the juvenile was moving forward and when he came out of a turn going left was aimed towards the Operator 1 on the jet ski.  Operator 2 pulled the lanyard to kill the motor and Operator 1 hit the throttle to try to avoid the collision but was still struck in the stern of the jet ski.