It’s kind of both actually. First, we need the engine to support it. Then it needs to be exposed in the Editor UI somehow.
An open source contributor already had a go at implementing this:
Unfortunately, they weren’t able to address my concerns about performance so it was never completed and merged.
An original feature request for this was actually logged by me waaaay back in 2016:
Since it can be worked around using the parent-child technique you mentioned, it was seen as relatively low priority. But I think we’re getting closer to the point where we should implement this feature.
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