data validation dependant on previous cell

I have a worksheet that I'm going to use as a data/keyword driver in automated testing. This worksheet will be used to work out the test case steps and the keywords for each test case. the worksheet will be named the same as the testcase id it represents. These are the columns I want to populate: PARENT (to have these possible values:Browser, Browser Page, Browser Window, Browser Dialog, Dialog, Window);
PARENT TYPE (so if its a Browser then it must contain a list of urls from a list head in worksheet, if its a Window then it gets this from a list of valid values for windows only - like winedit yet cannot have browser values like webedit);
KEYWORD- this found in the "Descriptions" worksheet and is the keyword reference to the object definition outlined in this worksheet (that is unique in combination with the url/browser/window/dialog: so for instance for a browser, the row that this is defined in will have the following cells each in succession will contain :- browser URL, browser|Dialog|Browser Dialog|Window title, page name, 'keyword1|object definition','keyword2|object definition','keyword3|object definition' etc);
EVENT - which can have this list as a validation: Activate,CheckProperty,Click,Close,Exist,Launch,Navigate,Run,Select,Set,SetSecure,Sync,Type. Obviously some of these events are not valid for all object types but if you can show me how to do this for 'Parent Type' then the same method would apply here?
VALUE a free text field

and I will add others when I know how to do the above.
What I need to know with examples as I'm not a very good theorist.....

1.I can create the 'PARENT' entry by a simple data validation list but I dont know how to make the 'PARENT TYPE' dependant to the Parent - as the example above outlines.
2. How to only show the keywords available (in a dropdown) for the URL that is held in my URL worksheet, But if its not a browser like a dialog then get the keywords from the next field since the URL value would be blank and the title exists for any parent)

I am assuming all the Columns can be populated using different versions of the 2 methods I would need to find out from anyone on this forum. I am no excel expert but I can do most things once given an example or topics to search with.
I would appreciate any help

Thanks
Joe

attached is an example that my friend ansho sent me but I am using a different approach (the password for the vba is relevantcodesone) (couldn't attach file)

please use the file attached inline