Caitriona Palmer was given up for adoption in Ireland in the 1970s. She had a happy childhood and never felt the need to find her birth mother. But when she was in her 20s, she started working in Bosnia exhuming mass graves and the experience moved her to look for her birth mother. Today they have a good relationship, but it's still a secret to some in their family.

Karen Guthrie is a film-maker from Scotland. On the surface she has a pretty ordinary family, but when Karen discovered that her dad had a secret second family in the east African country of Djibouti she decided to film a documentary about their story.

Phyllis Whitsell is a nurse who faced a heart-wrenching dilemma that few of us will ever have to confront. When she was a few months old, she was sent to an orphanage, and a few years later, she was adopted. Her new family never spoke of it, and Phyllis thought that her birth parents had died of tuberculosis. But Phyllis had a strange intuition.