Make vocabulary sub-categories collapsible

Is there anyone who can help me make vocabulary sub-categories collapsible?

Currently it is possible to collapse vocabularies, but in a vocabulary with many parents and children it would be great to make parents (sub-categories) collapsible as well:

vocab - parent 1 - child 1.1
- child 1.2
- child 1.3

- parent 2 - child 2.1
- child 2.2
- child 2.3

Much similar to the Taxonomy Super Select module.

Thanks.