I have a simple windows form with one primary BO and two child bo's. I have MaintenanceFormToolStrip on the form. 

Yeap, sounds very confusing.
The fastest way to deal with this is to create a small sample application using the StrataFrameSample database to simulate the functionality you are looking for, then post it in the forums so we can see and fix.

You said you have 1 parent and 2 child business objects, here are several questions:

1. Are you using any control in the form binded to the child BOs?
2. Are you setting the relationship between child and parent BO somewhere?
3. Are you handling any BO or Form events related to the BO navigation or alike?

As you can see this could be very tricky to figure out without looking at the code, but once you understand the Business Object logic and concept it is very easy to manage multiple relationships.  There are several post in the forums related to that topic.

Edhy Rijo