Currently, the only way to create child tickets is through Tasks, or by linking a ticket to a parent ticket. We have a multitude of use cases where we would benefit from a "create child ticket" button.
One example: End user submits a ticket to unlock their AD account, and they mention that their account was locked out because their keyboard needs to be replaced.
Another example: New user setups! Not all new users have the same needs, or get the same access (action rules and tasks don't really work for this). When we get a new user request, we need to be able to create child tickets manually to address individual needs.