For those who do not understand what a closed adoption is, you'll want to consider that this is where the parents adopt a child, but the biological parents are kept private. There are many reasons why both sides would want to protect their child from this, but it is also a good option for those who are young mothers who wish not be looked up. It's done mostly with young children or infants.
The closed adoption is the way that it always was done. Often now you'll find people wishing to find their biological parents, because being open or closed was not an option for most agencies. It was very clear-cut. You would give the baby up and that was it. It was over with. Even with a closed adoption, the child still may be able to contact the biological child. You'll want to consider that when the child is at age, they have the right to look into their own files. If the biological mother allows the records to be released, then the child will be able to find information on why they were adopted and the names of its biological parents.
There are some perks and disadvantages to closed adoption. It's nice to keep the privacy if you are giving up a newborn. This way it's easier to cut yourself off. You'll want to continue to keep your privacy, so that you don't have to deal with some of the hurt feelings, however, open adoptions are become more and more popular. This way the child will be able to appreciate the situation and also see both points of view. They can understand why they were adopted without having hurt feelings.