Moving a task from Milestone to another Milestone

Moving a task from Milestone to another Milestone

Is there a way to to move a task from milestone's task list to another milestone's?  For instance:
 
Milestone 1
         task list: A
                 task: Cat
 
Milestone 2
         task list: b
                 task Dog
 
How would one go about moving the Task "Dog" from task list b in Milestone 2 to be with Milestone 1, Task list A?
 
Thanks