Inherit custom fields from parent

Hi, is there a way to have child pages ‘inherit’ custom field values from their parents?

I have setting some custom fields and I would like them to filter down to the children, unless the children over-ride them.

In effect, I don’t need the values to be set in the child pages… but I need to refer to the parent values if the child does not have its own. (confusing, huh?)

Thanks for any pointers.