Uninstalling multiple msi's using parent msi custom actions

Question

Hie I have made an msi package that contains 4 other msi's.When the parent msi finishes installing,i insatll the child msi's sequentially.I managed to do this using orca and editing the install custom action from 1042 to 1234. I would also like to do the same process on uninstalling the parent msi.I would like to uninstall the 4 child msi's that were installed when the parent msi was installed,then the parent itself (chained uninstall).. When i use uninstall custom actions so that it points to to a .exe that will run the uninstallation of the child msi,the custom action is not launched.I've tried so many things but still to no avial.. please assist...on how i can best i can go about this using msi's..
I used c# for my coding..