When confidential adoptions were the norm, adoptive parents and adoptees seldom knew if the birth parents had other children. Today, even those families who do not have routine or direct contact with their children’s birth families have some knowledge of them.

Adoptive parents receive information at the time of placement, and non-identifying letters sent annually through a confidential intermediary reveal changes in the birth parents’ families — illnesses, deaths, marriages, and births. It isn’t unusual for adoptive parents to know that their child has siblings in other adoptive families or who are being raised within the birth family.

Parents who know their child has biologic siblings have many questions to contend with — their own and their child’s. They wonder what to call these siblings or how to explain why the birth parents relinquished one child and raised another.

A Review of Genetics

Children are often able to tell their adoption story and introduce their birth relatives at an early age. However, they can’t fully understand what adoption means until they comprehend the basics of reproductive biology. Developmental specialists say the cognitive development necessary to understand this is attained around the age of four.

Now, it’s tricky for a child to understand that she grew from the sperm and egg of one couple, was born to that couple, then came to live with another family — that, in one sense, she has two mothers and two fathers. The biological explanation of sibling relationships is even more complicated. It requires a child to understand more than reproduction; it requires that she understand basic genetics.

She needs to understand that a child gets half her chromosomes from her biologic mother and half from her biologic father. This is what makes them her biologic parents. This formula also applies in the case of embryo donation, in which a fertilized egg is implanted in a host mother (often the adoptive mother) who carries the baby and gives birth. A child’s biologic siblings are siblings because they received chromosomes from the same mother or father.

Generally, the cognitive ability to understand genetics comes around the age of nine. Before that time, it may be confusing for a child to be told that children who live in another family with other parents are his siblings. To a child, brothers and sisters are the people who share the experience of growing up together.

It can be difficult for a young child to think of a much older brother or sister as a sibling if they did not grow up together — even if they were raised by the same parents, in the same household. While adoptive parents and birth parents may long for their children to have a close relationship, or at least an understanding of each other’s significance, this isn’t going to happen by labeling them as “siblings” before they are old enough to understand what that means.

When children are young, it’s better to describe them in terms of their relationship to the other parents, by saying something such as, “Harry is your birth mother’s little boy.” Just as the four-year-old who has been told about reproduction will one day ask, “Did I grow in your tummy, Mommy?” the nine-year-old will one day ask, “Does that make Harry my brother?”

Open Adoption

A biologic connection may provide a reason to develop and maintain a relationship, but it is not enough on its own to forge a relationship. Biologic sibling relationships are no exception. Adopted children will develop relationships with their birth siblings if they have ongoing opportunities to do so.

Most parents find it easy to encourage relationships between their children and children in another family when those children are very young. As children grow, they develop their own interests and preferences for playmates. A shared biologic history may not be enough to get two children through an afternoon if one likes chess and the other likes horseback riding. It may not be enough if they see each other only once a year. Parents need to have reasonable expectations about the level of closeness children will feel for one another.

Furthermore, as children reach adolescence, they begin to be able to imagine what might have been. A 12-year-old may come to see how his birth mother struggles to make ends meet for the children she is raising and realize that her decision to relinquish him was made with his best interests at heart. It could also leave him feeling guilty that he had an opportunity that his biologic siblings didn’t have.

Some children even want to intercede in the lives of their birth siblings by asking their adoptive parents to let the siblings come and live with them. The 12-year-old may also wonder: If my birth mother’s life hasn’t changed since I was born, why didn’t she place other babies for adoption, too?

Wondering What’s Changed

The question of why a birth mother relinquished her child is the most profound one in adoption. Birth mothers must overcome the maternal instinct to protect and care for a newborn baby and respond to an instinct that says only through relinquishment can the child be cared for and protected.

We tell our adopted children that for whatever reason — economics, lack of support, lack of maturity — their birth mothers could not take care of any child born to them at that time in their lives. Their social, emotional, or economic circumstances may have improved by the time other children were born to them. They may improve in the future. They may have made — or may make — a different decision about a child born in better times.

Sometimes, though, it’s the birth mother’s perception of her circumstances that changes. And it happens that a birth mother who has once experienced the pain and grief of relinquishment is not willing to take it on a second time. Nonetheless, the important factor is the kind of commitment the birth mother believes she can make to raising a child born to her at that time in her life.

Parents can help a child understand a birth mother’s differing decisions by finding an example in the child’s own life. Perhaps there was a situation in which he did not feel able to take on some responsibility, but a little bit later, a slight difference in circumstance or experience left him feeling ready for that responsibility.

Perhaps there was a time when the child took on a responsibility even though, deep down, he knew he wasn’t ready for it. With empathy and thoughtful discussion, both child and parents can develop a greater understanding of the circumstances that can lead a birth mother to place a child for adoption, and of how those circumstances can change over time. In the process, they will not only add depth and detail to the story of how they became a family, but will also reinforce their child’s sense of worth.