re: Doubt this has happened to a TDer before.

Sounds like they never told him he was adopted. I may have overlooked you saying otherwise. But if they hadn't, I can understand them not wanting to do it even when he was 27.

At first I thought, why not reach out to the wife, surely they would want to know, but now might be too soon. And you surely wouldn't get a warm reception like your wife is probably imagining.

3 kids finding out their grandparents aren't really their real grandparents would be tough too.