Global Child Thrive Act of 2019 This bill reauthorizes for FY2020-FY2025 programs to provide assistance to orphans and other vulnerable children in developing countries. The bill also requires the U.S. Agency for International Development to direct relevant executive branch agencies to incorporate early childhood development into current programs and promote inclusive early childhood development in partner countries. Such actions to promote early childhood development shall build on existing U.S. plans and strategies and aim to (1) prevent unnecessary family-child separation, (2) assist families with children with disabilities, and (3) help countries transition from child care protection systems that rely on residential care (such as orphanages and children's homes) to ones focused on family-based care.