My Mum and Uncle are both adopted. They have always known, they can't even remember the first time they were told. My Nan has always said that she was supportive of both of them finding their birth parents. My Mum has never bothered as Nan was the one who raised her so Nan is her Mum. My Uncles birth parents made contact about 10 or so years ago and they now see them pretty regularly. Being open about it was definitely the best thing.