The DOBs are entered appropriately but some do not appear next to individuals in the “People” view and do not appear on reports, while some do. On the events dialogs it all looks the same between individuals where it does work and where it doesn’t.
The list of people is from the Grouped People view.
The Surname appears next to the ▸arrow. Clicking on the Surname opens a list of people with that Surname with all of their details similar to person with the ID I0012.
Right-clicking in the list allows you to open, or close, all nodes.
The Issue is that the highlighted person has a Birth (with date) listed in the Events gramplet. But that date does not show in the Birth Date column of that expanded portion of the Grouped People view.
You can confirm the Unknown role by expanding the window (or turning off the sidebar in the View menu) so that the Role column is showing in the Events gramplet of the bottombar.