Families can be a bit of a minefield and no one can predict what kind of response you're likely to get. I have 2 older half brothers that I believe live in France, my dad's first wife who was french upped and left with the kids one day while he was at work. I've always known about them but never felt any urge to have contact, just as well probably as I wouldn't have a clue how to find them. My husband has a son born when he was 18 whom his first wife banned him from telling their two kids about, even though they are now adults they know nothing of his existence, yet my husband, his ex wife, his parents, brothers and sisters, me and my kids all know of him, tis madness. He thinks his daughter would be really keen to contact her half brother if she knew he existed and yet she's still kept in the dark because that's what her mother wants.

I know i have a half sister, but i haven't seen her since i was a baby, so i don't know her at all. I've heard she has a son, basically making me an auntie... a part of me would like to get to know them, but i don't know her second name, don't know where she lives, don't know anything about her, but i know she hurt my father... and she's gone this long without contacting us (we haven't moved and our names haven't changed) so i'm 99.9% happy not knowing. It's a shame though, as my real family is so small.

Might be a bit controversial but I dont think it should be up to the parents to choose whether their children know each other or it. I believe the children shoud be told and allowed themselves to decide whether or not they are in each others lives.