Dynamic Todo list

Hi all, i have a todo smartsheet and assign task to my team (more that 20 users). I want to create a personal todo smartsheet per user for each of them in order to keep the open tasks and when i add in my sheet a new task for the user No.1, automatically copy this in user No.1 sheet and when change something or close the task update it the same in my sheet. Until now, i can copy automatically the line to the one i assign the task but i cant make it update it in real time from the both sides. Any suggestion?