I have read the interview from his dad " horrible man " " there's never going to be any reuniting " etc etc.
I am shocked that after marrying and having two children they never attempted to reclaim him.
All I can gather is the illegitimacy of Jeremy must have stung both still.
Then again he had gone to a good family, Nevill and June were good people.
I would imagine that Jeremy's brother and sister have had lots of curiosity about him over the years. Only natural I suppose.
The only thing I can say, by way of supporting them, is that when people, ie birth patent(s), 'sign on the dotted line' they're agreeing to relinquish the child, and all rights to it, to its new parents. That, back then, was a legal fact. It has nothing to do with the moral or emotional, and it's a fact that many grown up adopted children, in search of birth parents who may choose not to know them, are still having to face. Whether or not the answer they find is worth the search, only they can tell.
This is something JB, as an adopted child, would have faced. Certainly, there was a chance that they may have reached out, but an equal chance there'd have been rejection -perhaps guilt so deep -and rightly so! His illegitimacy was never his fault!- on their part, that they didn't feel they could face him? Their problem, though. Not his, but he wouldn't have understood that. His arrest and conviction would have been perfect justification for rejecting him a second time. After all, in their eyes, they'd done their best for him, hadn't they? He was no longer their responsibility..................I fail to see how his siblings aren't curious, though. It may be a question of waiting until their parents have gone before acting on it?