I have a design where an Invoice can have multiple Payments.  A Payment form is setup to be a naturally linked subrecord of an Invoice.  However, Payments can occur outside of an Invoice, such as when a cash drawer transaction occurs without a sale taking place (such as an expense payment).

I'd like to be able to run a report showing all Payments for a particular date.  For Payments linked to an Invoice, I'd like to be able to pull some of the Invoice data into the report as well.  Is there anything that allows me to get the Parent record with only the Child record in hand?  If there is, I'm hopeful that it will allow me to solve the reverse problem, i.e. determining if a Payment record is an orphan.