Get count for all terms inside a parent term

I am trying to get the post count for a term and it's child terms. I tried it with pad_count= true but this seems to have no effect.

My term stucture is like the following:

- term 1: 10 posts
- term 2: 1 post
  -- subterm 1: 4 posts
  -- subterm 2: 12 posts
- term 3: 4 posts

This is my code:

$args = array(
  'pad_counts' = true
);
$terms = get_terms('category', $args);
foreach($terms as $term) {
  var_dump( $term-count );
}

For all the terms without children this works just fine, but for the "term 2", I want to get the counts of itself and it's children combined. In my example this would be 17. The code only gives me 1, though.

Any Tips?