I guess my first question is why do you have the same checkbox in three tables? I should think you wouldn't need that. It's very possible that I'm not thinking out-of-the-box enough, and perhaps there's a really legit reason for needing this. It just seems to me that this breaks table normalization rules.
Regardless, you could create a query that included the Individual check boxes from all three tables. On your form, put all three check boxes. Hide two of them. Then in the AfterUpdate event for the non-hidden checkbox, set the value of the two hidden checkboxes to the value of the non-hidden box like:
me.chkNonHidden1 = chkVisible
me.chkNonHidden2 = chkVisible
That's one way to do it... I could probably come up with some more if this doesn't solve your problem.
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