Adopted

I would think it all depends on the child and parents, some parents who have adopted will be afraid the child will be wanting their birth parents instead if them and some just don't want to tell the child or adult that they are adopted.

If I was adopting a child at birth, I do not think that I would tell him/her about the adoption : a plenary/complete adoption in my country puts an adopted child on the same rank than any natural child, and the birth certificate is modified to tell that he/she is your child, so why would I tell to this child that he/she was adopted ? At 30 years, you cannot adopt somebody without his/her consent. You can still recognize him/her as your child, but it is something else... and a bit late... but it happens times to times.

if i am to adopt, i will tell the kid.

For me, I will tell my adopted child when she/he is still young, telling him/her that I adopt her and tell her the reason why I adopt her/him, tell her whereabouts and later on, I'll tell him also where her/his parents are but my treatment for him/her is just the same as my natural children.

I am not adopted so my opinion is just based on what I feel. I think it is good to let the child know when he/she is old enough to understand. I would say it is better to let the child know about it when they are in their early teens or earlier. Sometimes, there are adopted kids who fail to see the good done to them and see the "confession" as an act of betrayal especially if they feel that it was done to keep them in the dark.

Soap operas have exaggerated the notion of adoption and made it a major plot for a usually complex story. Glad that you accepted it with open heart. Do you wanna know your biological parents?