Is it possible to enforce that you cannot create/save a parent object until you have connected to it at least one child object?

Issue

this is not possible in the out-of-the-box product. When you create a news object, first only the first layout tab will appear (where you can fill in the news object fields). After you save, then the relationship tab appears, where you can continue to edit the news object by adding attachment objects to it. There is even a warning about this, when you create the layout for the news object, see attached image.

The article at https://learn.liferay.com/w/dxp/liferay-development/objects/creating-and-managing-objects/relationships/defining-object-relationships#making-relationship-fields-mandatory seems to describe something similar, but it's the other way around. That is, you can enforce that, when you create an attachment object, you need to provide a parent news object that it belongs to (otherwise you cannot save the attachment). But it's not possible the other way around: when you create a parent object entry, you can enforce that you create/link at least one child object entry to it.