Q: When I adopted my two-year-old son, I was told that he has a biological sibling who was adopted by a family who lives in another state. My son is my only child, but his brother has adoptive siblings. How do I explain this to my son? How and when should we introduce the children to each other?

A: Research shows that siblings are very important to adoptees–many would rather find birth siblings than birth parents, and sibling relationships often continue after the initial emotion and curiosity over finding a birth parent has passed.

The first step would be to get in touch with the other family and work out starting parameters and language. You might begin by exchanging holiday cards and photos, then decide to meet once a year.

Show your son the photos. You can tell him, “This is your brother, because he shares with you the same birth mommy in Guatemala. Both of you grew in her tummy, and she chose our family and his family to be your mommies.” You can explain that siblings are made both by birth and by adoption, and that his birth brother has adoptive brothers and sisters.

These concepts probably won’t make much sense to a child as young as your son, but he will begin to grasp them around the age of three or four. Even so, you’ll want to start showing him the photos, and talking, so that hell grow up with the idea of having a brother.