Background Large‐scale population studies demonstrate an association between mothers’ deaths and child mortality in both lower and higher income countries. The authors estimated children’s deaths in association with mothers’ deaths from breast or cervical cancer, 2 common cancers in low‐income and middle‐income countries affecting women of reproductive age, to develop a comprehensive assessment of the death burden of these cancers. Methods A Monte Carlo simulation model was devised whereby women were at risk of dying from breast cancer, cervical cancer, or another cause. Compared with children who have living mothers, children of women who die before they reached age 10 years have an elevated risk of death from all causes. Therefore, simulations were conducted, and the impact of mothers’ deaths from cervical and breast cancer on associated child mortality was quantified for Bangladesh, Burkina Faso, and Denmark (benchmark analysis), then the analyses were extended to all African countries. Results Benchmark estimates of child deaths associated with mothers’ deaths from breast and cervical cancer resulted in an increment in cancer‐related mortality of approximately 2% in Bangladesh, 14% in Burkina Faso, and less than 1% in Denmark. The model predicted an increment in comprehensive cancer deaths when including child death estimates by as high as 30% in certain African countries. Conclusions To the authors’ knowledge, this is the first study to estimate the impact of a mother’s death from cancer on child mortality. The model’s estimates call for further investigation into this correlation and underscore the relevance of adequate access to prevention and treatment among women of childbearing age. It has been demonstrated in different geographic and socioeconomic settings that children of mothers who die have a higher risk of death compared with children who have living mothers. The model estimates in this study identify an increment in comprehensive cancer deaths when including child death estimates of up to 30% in certain African countries, and the predicted results call for further investigation and underscore the relevance of adequate access to prevention and treatment among women of childbearing age.