Have you tried the Report Options for the Journal Report on the "Tags" tab? Since you are mentioning events for children, you might try the settings I use:
- Applies to: Only children that are carried forward
- Include only: Birth Death
- Format: He was born in
If a child has their own section (is carried forward) then in the parent's section the report only lists the abbreviated events checked/included, i.e birth/death. That avoids some repetition since all that child's events will be output in their own section. But if the child does not have their own section then all the tags selected for the report are included/repeated for that child in the parent's section. With these options a particular child's data will always be there, either in their own section or repeated within their parent's section. There will still be some amount of repetition within a parent's section, but I know of no way to avoid that and still output all children's information somewhere.
Of course, if you do not want to replicate any child's events in a parent's section you could check the option:
But then as you have noted, if the child does not have their own section (does not themselves have children) then their events will not appear anywhere in the report.
Hope this gives you ideas,