How can I get the specific GroupHeaderControl with a given Group or CollectionViewGroup?

How can I get the specific GroupHeaderControl with a given Group or CollectionViewGroup?

The title basically says it all. I am trying to get to the GroupHeaderControl to make some changes whenever a row within the group is clicked. I am able to navigate to the CollectionViewGroup and Group, but have no idea how to get to the GroupHeaderControl. Any help would be appreciated!