I am adopted too. I love my mother and father as much as I love my kids and although my nightmare brother exasperates me we both know we'd help each other hide the bodies and would, and indeed I have, perjured ourselves to save the other. He and I are not related. He is a total waster, I am not.
He's a good bro now but still a liability at nearly 40. I was head boy, he was expelled. I have a great house / life - he's in rented. The mismatch between his natural state, my aspirations, and our shared adopted parents aspirations has marked us all and is not to be taken lightly. Nor is the different family dynamic to people who share your genetic characteristics to be written off, Now I have my own children, I recognise and understand genetic traits even the most empathetic parents can't understand - and mine did not.
40 years on, my parents have two kids who've followed them 200 miles from manchester and we will all love each other for ever, but it's not easy.