Motherhood is common among female sex workers (FSWs) and many have at least one biological child. People who inject drugs (PWID), men who have sex with men (MSM) and transgender people (TG) are also part of families and have at-risk spouses and children in their households. Stigma and discrimination towards key populations (KP) can negatively impact their children’s access to health, education and protection services. Program data from Cameroon, Ethiopia and Tanzania reflect positivity rates of 4-6% when children of FSWs are tested for HIV. Access to early infant diagnosis (EID), HIV testing and treatment and other critical health, social and economic strengthening interventions for children of KP and their families must be improved as a priority.