Tell or not?

Laurendag

So this is going to be a long one.

My Dh has a child from a previous relationship that was put up for adoption because of the mothers wishes. Dh tried to get LO (Luke) but due to some laws, since Dh and mother werent married he could not stop her from putting Luke up for adoption. (Something I dont understand but thats another question for another day)

Now Dh and I are expecting a child and Im torn between telling our LO about his older brother or not. Ive mentioned it a few times to Dh but he is equally as confused about it. Would it be better to tell him from the beginning should Luke wish to contact us when he is older? Or should we not incase he doesn't? Im lost because on one hand, if we don't tell him and it comes out later it might ruin his trust in us, I would certainly feel betrayed. But on the other hand, if we do tell him and Luke never contacts us, will he be heart broken to have never met his older brother?

Luke was adopted by friends of the mothers parents and the adoption is open, however, the mothers parents refuse to give us any chance to speak to the parents about seeing him. (Which the mother does, every few months) We do get updates and a few pictures once in a blue moon from the mother. So without being able to contact the adoptive parents we will have no way of knowing if we will ever be able to meet him.

Is any of this making sense? If not Im sorry but any input would be appreciated.