TreeView Check/UnCheck all child or Parent if one child is checked in c#

I found a lot about treeview and checkboxes in treeviews...

but one thing seems to be undiscussed.

I have my treeview like

[x] Foo
 L [x] One
 L [x] Two
 L [x] Three
[x] Bar
 L [ ] One
 L [x] Two
 L [x] Three
[ ] Hello
 L [ ] One
 L [ ] Two
 L [ ] Three

Now when I check my parent checkbox e.g. Foo than all child get selected. Also they get deselected by unchecking Foo. To do this I have this Method

private void TreeView1_AfterCheck(object sender, TreeViewEventArgs e)
{
    foreach (TreeNode childNode in e.Node.Nodes)
    {
        childNode.Checked = e.Node.Checked;
    }
}

I tried a lot with using count and others but could not achive what i'm trying to achive.

So what I want is, when I check Two in TreeNode Hello than Hello should get checked. Without checking One and Three. Check-/Unchecking Hello should select/deselect all childs.

Is this even possible?

Because when Hello gets checked, it fires the TreeView1_AfterCheck-event!

So my Question actually is:

Can I achive the above described behavior?

Ask me if something is unclear.