HAMMOND, Indiana — When Lori Townsend is missing her daughter particularly badly, sometimes she texts her old phone number, “Hey!”

When the inevitable “Who’s this?” comes back, Townsend explains that the person’s number used to be her daughter’s and that she was murdered by a serial killer. The person on the other end will say some variation of, “I’m sorry for your loss.”

But two years ago her daughter Afrikka Hardy would respond. There were hopeful exchanges about applying for jobs or enrolling in school. There were more than a few deeply private conversations that made the pair seem more like old friends than mother and daughter. There were plans to come home for the holidays.