Grouping Items and Parent/Child should be two different functions

The grouping of items in the side panels should be a separated mechanism from the parent/child function.

Reason:
To be able to group items as “types”, add an item to multiple groups, and at the same time be able to add the item as a child of a timeline item (Event).
As it is now, people will need to create multiple items “of the same type” and link them together to be able to do something like that.

for example, I have ships that group under both Owners and different Lines, but I would also like to add them as a timeline item (child objects) to different voyages.

or, I have multiple Ports, I want them grouped by location under Cities or Counties, but I also want to add them as timeline items to different voyages, sometime as First Port of Call, some times as Last Port of Call, and other times as one of multiple Ports of Calls, I also have Crew lists, Manifests, etc. that I want to add as child items to a voyage (main event), but that I also want to group under the type of item they is, but as it is now, I must create an extra Event for each Item I and if I want to create a main event for collection data for i.e. a person, a company and a ship, I actually need to create 3 or more extra items to manage it, if I want the periods or dates of those items to be visible in the timeline…

So either I can sort the items under a “group” or use it as a child item in the timeline, I can’t do both if the Parent item in the timeline differ from the “group”.

…or at least support multiple Parents for a child item…