Parent and child table relationships

Hi ,       I have list of four tables and I want to delete data from those tables. There are child tables under it and  I see  more child tables under those in hierarchy.
 
There are two methods to  delete the data either delete the data from all child tables in  hierarchy or disable the foreign keys.
 
I don't want to disable the foreign keys but I am trying to delete the data from child tables  however the child tables have FK...so It will not allow to delete from child table.

Is their a query that will list all the child table relationships on those four parent tables in  hierarchy and from from where I should start the delete.