I have a transaction which uses something like 10 business objects and needs to save them all out at the end of a bunch of processing.  There are parent/child relationships with almost all of these BO's.  However, one BO may be involved in a few parent child relationships.  This means in one case it may have a certain parent where in another case it would have a different parent.  Whether this is good design or not, that's what I have to work with...

Now, I know that there are issues when mixing the parent/child relationships and transactions on BOs.  Should I just assign the foreign keys manually in these cases?  If so, how do I do this correctly?  At the time I need to assign the foreign key the primary key on the parent hasn't been saved so it has a negative value in it still.  What is the best way to approach a situation like this?  I feel like I keep running into dead-ends.