>> I understood and agree with everything you said except this....

....If that's the case, I see no problem telling your users at the point of trying to add the second child: "you have to save the parent, the
first child and the grandchildren before creating the second child." (Worded differently, of course.) "Do you wish to do this?" <<

Rich, I was certain I was not getting my point across, but you have grasped it completely.

I'm sure you'll agree there is something counter-intuitive about asking the user to save at the creation of the 2nd child (Assuming the sequence of events I started with). It would seem random to the user. For now, I am going to see if I can come up with a presentable way to do that. Thanks much for the feedback