Invite reviewer

Hi ,

Could any one tell me what is the best way to implement the below process?

I am a user , I have to approve or reject a proposal. At the same time I can invite somebody to review the proposal.

In this scenario , where I invite somebody to review the proposal the control needs to be with me as well as with the reviewer i.e. the task should be assigned to me as well as the reviewer.

I can also invite more reviewers. When I invite more reviewers the task should be assigned to these new reviewers also .

Could you propose a solution for the above scenario?

Does the first task that you were assigned have to remain open while the additional tasks are activated?

Yes the first task is active .