In the board configuration of scrum and kanbanboards it's posible to base the swimlanes on either Queries, Stories, Assignees, Epics or Projects. 

We use a set of multiple projects in which the parent and the children reside in different projects. We would like to have a board with the parents (in our case a feature) and the children issues (stories), in which the parent and the children issues are grouped by parent.

So please make it posible to base swimlanes on parent issues.