find relation in dataset with c#

Question

hello, i`m programming with c# and sqlserver 2000, i have DATASET that contain all the tables and the relations between theirs. be given any column(supoose c1) in any table(supoose t1) in the DATASET, how can i know the child/parent column of this known column(c1)? or how can i know the parent/child table of this known column(c1)/table(t1)??? i want to emphasise, i have all the relation in the dataset already!!!!!! thanking you in advance koby