Hi,
The Entity field in the Transaction table will show the fullname of the Entity. The FullnName is contructed by the ParentFullName and Name field separated by a colon (Parent:Job).
Assuming you're putting this field on the Edit Customer screen, you can set a filter on the grid. Filter the Entity field and select Contains, Value from Screen for FullName. See below:
With this filter, if you go to the grid from the parent, transactions for all jobs will show since you're filtering for anything containing the parent name.
Hope this helps.
- Adam