Mam is the antagonist in the novel, working nights in a pub and later in a factory. She is physically and verbally abusive to her children, expressing shame over Ada's clubfoot and taking out her frustrations on the kids after her husband's death.

Jamie is Ada's younger brother, six years old at the start of the novel. Initially malnourished, he becomes healthier with Susan's help. Jamie is interested in airplanes and looks to Ada as a protector, eventually leaving their mother with her.

Susan is a single woman living in Kent who takes in Ada and Jamie, despite claiming she never wanted children. She provides love, stability, and support to the siblings, helping them heal from their traumatic past with Mam.