How to compare fields of two issues connected with a relationship (e.g. parent -> child)

[Chris Smith]

Hi, 

   I am looking to find issues where a field on a parent and child do not match. For example a custom field called bounciness. I have many Epics (with bounciness) and most of them are connected in parent->child relationships. So if I want to find all the issues where

parent->bounciness  != parent->child->bounciness

How would I go about doing this with scriptrunner etc?