Angular 2 prevent click on parent when clicked on child

You need to use stopPropagation() for checkbox event:

<input type="checkbox" [ngModel]="task.taskStatus" (ngModelChange)="changeTaskStatus($event);$event.stopPropagation()" />

It prevents further propagation of the current event in the capturing and bubbling phases. You can read more here. Also, you probably need to add stopPropagation() to click event of checkbox, but I’m not 100% sure:

<input type="checkbox" [ngModel]="task.taskStatus" (click)="$event.stopPropagation()" (ngModelChange)="changeTaskStatus($event)" />