At the time, in 1989, there were no medications or treatments for AIDS in Zambia. So Billy nursed her at home in their kitchen. Soon, she couldn't walk or even stand.

Growing up in Kitwe, Zambia, he was one of 13 children. During meals in the family’s three-room house, he always sat next to his twin sister and best friend: Charity. “We [would] eat from the same ...

Night had fallen hours ago, but Billiance Chondwe was not slowing down. On Feb. 20, he frantically tapped out texts on WhatsApp, dialed distant acquaintances and left voice messages from his home in ...