Viewing a Look-up Field with a formula as a table in Detail View

Hi all - I have a small Family table that links multiple family member contact records to one row. I would like to then show the individual Activities from each contact record in the same column on the Family Table. The Activities are also lookup fields from an Activities Table.

The problem is that the simple formula I use here makes it so that the Activites don’t show up in a nice table format like the contact records do when I expand the record. Does anyone know a way around this so that?