Accessing child records from parent and vice versa

Hi,
I have created a custom record called "Company Preferences". On this record are several subtabs "Holidays", "Support", etc. there will always only be one record for Company Preferences.

I also created a custom record called "Holidays" and made this a child record of Company Preferences. Works nicely. When in the Company Preferences, I can click on the subtab "Holidays" and I see a list of Holidays with a 'New Holidays' button, edit and remove links, etc. I can add and remove holidays at will. Very nice and simple for the HR person who would be responsible for managing.

Essentially I want to get the list of these holidays (all records) accessed in each new Support Case that is created (on PageInit) so I can check to see if a holiday is upcoming or in affect (when calculating response against customers who have a business-hours only support plan). I know I can do this simply by creating some field and filling it with dates, or by simply creating an array in javascript, but ultimately it will be someone else managing this and the person managing holidays knows nothing about how it impacts support cases and the Support manager should