Creating Merge Requests from Parent for Fork to Parent
Created by: ekristen
You should be able to create merge requests from fork to parent from the parent's merge request form. The dropdowns should populate with the forks you have access to.
The typical workflow these days is developer forks parent project, hacks, commits and then submits merge/pull request back to the parent.
GitHub supports this ability and I think it only makes sense. No reason why you have to do it from your fork.