Connor Pierce is standing in the cluttered upstairs bedroom where he found his mother's body the evening after Thanksgiving two years ago. Silent and largely undisturbed, the room in Gwinnett County is still choked with the stuff his mother hoarded in the final years of her drug addiction: brightly colored party cups, her purple recipe notebook, a pair of crutches, laundry baskets brimming with clothes and her children's elementary school projects.

Connor’s 33-year-old mother, Stephanie Futrell, overdosed on heroin spiked with fentanyl, a short-acting pain reliever that is as much as 50 times more powerful than heroin. For years, doctors have prescribed fentanyl in the form of patches and lozenges to treat severe pain, typically from advanced cancer. Lethal in tiny amounts, drug dealers are now making it in clandestine labs in Mexico and mixing it with heroin to boost its euphoric effects, often without the user’s knowledge.

In March, President Barack Obama appeared at a summit in Atlanta to bring attention to the nationwide painkiller and heroin overdose epidemic that killed more than 28,000 people in 2014, more than any year on record. Obama noted that more people are now killed from drug overdoses than traffic accidents. The month after the president appeared in Atlanta, Prince — the songwriter and singer — died from an accidental fentanyl overdose at his home in suburban Minneapolis.

“I miss her,” Connor, 12, says of his mother, “but I don’t really think about it. I kind of think more positively most times.”