RadioGroup in expandablelistview

I'm trying to do something like this with expandable list view :

PARENT 1:
    - child 1 ( Radio Button)
    - child 2 ( Radio Button)
    - child 3 (Radio Button)
    - child 4 (Checkbox)
    - child 5 (Checkbox)
PARENT 2 ...

BUT: child 1,child2, child3 should act like a radiogroup. So if i check, for example, child2, child1 and child3 should be uncheked.

I've already managed to do this: some childs are with radio button and some with checkboxes. But radio buttons are not connected with each other and don't act like a radio group.

Can someone help me to solve this problem?